LifeKeeper® for Linux v4.5.0
Sendmail Advanced Message Server (SAMS)
Recovery Kit Administration Guide
Revision B
07/2004
Table of Contents
Reference Documents..................................................................................................5
Sendmail Configuration File.............................................................................................10
Configuration Requirements.............................................................................................11
Active/Standby Scenario..........................................................................................................12
LifeKeeper Configuration Tasks..............................................................................................17
Extending Your Hierarchy................................................................................................25
Hierarchy Creation Error Messages..................................................................................34
LifeKeeper for Linux
1
SAMS Recovery Kit
Administration Guide
Introduction
The Sendmail Advanced Message Server (SAMS) is a suite of commercial
messaging applications. These applications provide various services to
clients, such as POP and IMAP, as well as storing and transferring e-mail
messages.
®
The LifeKeeper for Linux SAMS Recovery Kit provides a mechanism to
recover SAMS from a failed primary server onto a backup server in a
LifeKeeper environment. Both LifeKeeper and SAMS ensure data integrity
throughout the course of the failover process without significant lost time or
human intervention.
Document Contents
This guide explains the following topics:
•
documentation and where the information is available.
•
your server must meet certain hardware and software requirements. You
should refer to the LifeKeeper for Linux Planning and Installation Guide
for specific instructions on how to install or remove the LifeKeeper
SAMS Recovery Kit.
•
configuration, you must understand your network configuration,
interface selection, mail user setup, hierarchy options and the SAMS
configuration tasks.
LifeKeeper for Linux
3
Introduction
•
LifeKeeper Configuration Tasks. A description of the tasks for
creating and managing your SAMS resource hierarchies using the
LifeKeeper GUI.
•
messages with recommended solutions.
LifeKeeper Documentation
The following is a list of LifeKeeper related information available from
SteelEye Technology, Inc.:
•
•
•
•
LifeKeeper for Linux Online Product Manual
LifeKeeper for Linux Planning and Installation Guide
LifeKeeper for Linux IP Recovery Kit Administration Guide
LifeKeeper for Linux Apache Web Server Recovery Kit Administration
Guide
•
•
•
•
•
•
•
•
LifeKeeper for Linux Informix Recovery Kit Administration Guide
LifeKeeper for Linux MySQL Recovery Kit Administration Guide
LifeKeeper for Linux NFS Server Recovery Kit Administration Guide
LifeKeeper for Linux Oracle Recovery Kit Administration Guide
LifeKeeper for Linux Print Services Recovery Kit Administration Guide
LifeKeeper for Linux Sendmail Recovery Kit Administration Guide
LifeKeeper for Linux Data Replication Administration Guide
LifeKeeper for Linux Network Attached Storage (NAS) Recovery Kit
Administration Guide
•
•
•
LifeKeeper for Linux Software Development Kit (SDK)
LifeKeeper for Linux Release Notes
Configuring LifeKeeper Clusters (available only from the SteelEye
Technology, Inc. web site)
LifeKeeper for Linux documentation is available on the LifeKeeper
Documentation CD that is shipped with the LifeKeeper Core software, and
at the SteelEye Technology, Inc. web site:
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SAMS Recovery Kit Administration Guide
Requirements
Reference Documents
The following is a list of reference documents associated with the SAMS
product and the LifeKeeper SAMS Recovery Kit:
•
•
•
•
•
•
•
Sendmail Advanced Message Server Reference Guide
Sendmail Advanced Message Server Installation Guide
Sendmail Advanced Message Server User’s Guide
Sendmail Switch Installation Guide
Sendmail Switch User’s Guide
Sendmail Manual Page
Sendmail, 2nd Edition by Eric Allman & Bryan Costales. (O’Reilly &
Associates)
•
Virtual Hosting with Sendmail (http://www.sendmail.org/virtual-
hosting.html)
•
•
•
•
•
•
Sendmail – An Internetwork Mail Router
Red Hat Sendmail Reference Manual
Sendmail Configuration File (/etc/mail/sendmail.cf)
Installation and Operation Guide by Eric Allman
Readme for Configuration File version 8.9
A Highly Scalable Electronic Mail Service Using Open Systems
(Sendmail)
Requirements
Before attempting to install or remove the LifeKeeper SAMS Recovery Kit,
you must understand the hardware and software requirements and the
installation and removal procedures.
Kit Hardware and Software Requirements
Before installing and configuring the LifeKeeper SAMS Recovery Kit, be
sure that your configuration meets the following requirements:
LifeKeeper for Linux
5
Requirements
•
Servers. The Recovery Kit requires two or more supported computers
configured in accordance with LifeKeeper requirements described in the
LifeKeeper Release Notes, which are shipped with the LifeKeeper
product media.
•
LifeKeeper software. You must install the same version of LifeKeeper
software and any patches on each server. Please refer to the LifeKeeper
Release Notes for specific LifeKeeper requirements.
•
•
LifeKeeper IP Recovery Kit. You must have the same version of this
Recovery Kit on each server.
IP network interface. Each server requires at least one Ethernet
TCP/IP-supported network interface. In order for IP switchover to work
properly, user systems connected to the local network should conform to
standard TCP/IP specifications.
Note: Even though each server requires only a single network interface,
you should use multiple interfaces for a number of reasons including
heterogeneous media requirements, throughput requirements, elimination
of single points of failure, network segmentation, and so forth.
•
•
TCP/IP software. Each server requires the TCP/IP software.
SAMS software. Each server must have the following SAMS software
packages (RPM format) installed:
•
smiswitchgui (Sendmail Switch)
•
smserver (Sendmail Advanced Message Server)
The same versions should be installed on each server. Consult the
LifeKeeper Release Notes or your sales representative for the latest
release compatibility and ordering information.
You should refer to the LifeKeeper for Linux Planning and Installation
Guide for specific instructions on how to install or remove the LifeKeeper
SAMS Recovery Kit.
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SAMS Recovery Kit Administration Guide
Configuring SAMS with LifeKeeper
Configuring SAMS with LifeKeeper
This section contains information you should consider before you start to
configure SAMS and examples of typical LifeKeeper SAMS configurations.
Please refer to your LifeKeeper Online Product Manual for instructions on
configuring your LifeKeeper Core resource hierarchies.
(SAMS does not allow multiple instances of itself).
Typical LifeKeeper SAMS Environment
The following figure illustrates a typical case of an active/standby SAMS
configuration.
Figure 1 Active/Standby SAMS Configuration
Mail
Mail
Mail
Server 1
Server 2
Server 3
Primary
Mail Hub
Backup
Mail Hub
DNS
Server
Switch,
SAMS
Switch,
SAMS
Config
Dirs
Config
Dirs
Config
Dirs
Firewall
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Configuring SAMS with LifeKeeper
Figure 1 illustrates how SAMS works in a LifeKeeper environment. An
active/standby configuration means that only one instance of SAMS can run
at one time within the LifeKeeper-protected pair.
In an active/standby configuration, one server acts as a primary mailhub or
mailserver, while the other server acts as a backup mailhub or mailserver.
The primary server runs the LifeKeeper-protected SAMS daemons, accepts
client requests, and transports email over the network and locally, while the
backup server does not run the SAMS daemons. In the event of a failure, the
backup server will take over the role of the primary server. The LifeKeeper
SAMS Recovery Kit will handle the change of control of the configuration
files and the message store database, and will restart the LifeKeeper-
protected daemons on the backup server. Once the primary server is restored,
it will function in a backup capacity.
In order for any mailhub or mailserver to qualify for use in a LifeKeeper
SAMS protected environment, it must meet the following requirements:
•
•
•
Configuration files, message store database, and mail queues must be
located on shared disks. The SAMS Recovery Kit requires that both
servers be able to access the shared mail queue directories and the lmtp
message store.
Note: If the database and mail queues are already configured on a local
disk, then one of the alternatives is to move the directories and files to
the shared disk and link them to the local disk.
The SAMS Recovery Kit also requires a free/unused shared file system.
The shared file system is used by the SAMS Recovery Kit for the storage
of configuration files and data files. The shared file system is required so
that both the primary and backup servers can run the SAMS applications
with the same data and configurations. This file system should not be
LifeKeeper-protected prior to the creation of the SAMS resource
hierarchy.
The SAMS Recovery Kit requires an alias - or switchable - IP address,
which must be under LifeKeeper protection and be defined on both the
primary and backup server. This switchable IP address is used by the
SAMS applications to connect with clients and other servers. It is
therefore very important that SAMS be configured to eliminate the use of
the hostname and instead use the switchable IP address in all
configuration files. If the hostname is used, client connections to the
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SAMS Recovery Kit Administration Guide
Configuring SAMS with LifeKeeper
server may fail when a switchover to the backup server occurs. Note that
the SAMS Recovery Kit does not require the switchable IP address to
have an MX record on the DNS server.
Protected Files, Directories and Services
The SAMS Recovery Kit protects the following configuration and data
directories:
•
•
•
/etc/mail
/etc/md
/var/md/store
If not located on a shared file system, the MTA and MSP queue directories
(e.g., /var/spool/mqueue, /var/spool/clientmqueue) must be manually moved
to the shared file system and linked to the original location on each server
before the hierarchy is created.
Any files that are not in the default locations as listed above (i.e. mailstore,
transaction log path and the Sendmail switch data directory) must be
manually linked to files/directories on the shared file system.
Note: The shared file system should always have the most up-to-date
configuration files.
The SAMS Recovery Kit will monitor and protect the following services
whether they are configured on default or non-default ports:
•
•
•
•
•
sendmail (default port 25, configurable via /etc/mail/sendmail.cf)
pop3d (default port 110, configurable via /etc/md/store/ms.conf)
imapd (default port 143, configurable via /etc/md/store/ms.conf)
samshttpd (default port 8890, configurable via /etc/mail/switch.ini)
perl sdap-server.pl (default port 9000, configurable via
/etc/mail/switch.ini)
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Configuring SAMS with LifeKeeper
Sendmail Configuration File
The following are a few more important points to note in the Sendmail
configuration file (/etc/mail/sendmail.cf).
Masquerading
Masquerading is used to translate an email address with a given hostname
into the address of the domain or that of another mailhub/mailserver.
Masquerading can be done at either the domain level or at the host level of
the mailhub/mailserver itself. If masquerading has already been established
to translate the hostname address into that of the domain, then it will not
impact the LifeKeeper SAMS Recovery Kit and you can continue using this
method. However, if masquerading is not used at all, then unpredictable
results will occur during and after a switchover. If masquerading has not
been used prior to implementing LifeKeeper, it is recommended that the
hostname address be masqueraded as the LifeKeeper-protected switchable IP
address.
Port Definition and the SAMS Recovery Kit
The SAMS Recovery Kit listens to the port specified in the
DaemonPortOptions entry in the Sendmail configuration file. If the port is
specified as a service name (e.g., smtp) then the port number is looked up in
the /etc/services file. If DaemonPortOptions is not defined in the Sendmail
configuration file, the port number defaults to the smtp port number defined
in the /etc/services file. If the smtp port number is not defined in
/etc/services, port number 25 is used. If the port is defined in /etc/services
and not in the Sendmail configuration file, you have the advantage of
defining a different port on both the primary and backup servers.
Daemon Mode (Red Hat)
If running on Red Hat Linux, be aware that the SAMS Recovery Kit does not
support disabling the Sendmail daemon feature. Be sure that the Sendmail
system configuration file (/etc/sysconfig/sendmail) has the Daemon option
set as DAEMON=yes.
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SAMS Recovery Kit Administration Guide
Configuring SAMS with LifeKeeper
DNS, Sendmail and LifeKeeper
DNS offers a mechanism (MX Records) for specifying backup or alternate
hosts for mail delivery. This mechanism also allows hosts to assume
mail-handling responsibilities for other hosts that are not configured to
accept mail, such as a null client. MX records also provide a mechanism of
forcing all mail to go to the hub machine or mail server. MX records specify
a mail exchanger for a domain name (i.e. a host that will process and/or
forward mail for the specified hostname). As an example, this is done by
adding entries into the DNS server as follows:
himalaya.sc.steeleye.com IN MX 10 relay.steeleye.com.
In the example, the server himalaya.sc.steeleye.com has an MX record that
will cause mail for this server to be delivered to relay.steeleye.com. The
server which is to be LifeKeeper protected should not have any MX records.
The LifeKeeper-protected switchable IP address that is used during the
SAMS resource hierarchy creation should be used for MX records instead.
Configuration Requirements
To understand the configuration scenario in the next section, keep these
configuration requirements in mind:
•
•
LifeKeeper hierarchy administration. When performing LifeKeeper
administration, the primary server refers to the location that the SAMS
instance is currently running. System administration takes place on this
server when creating a LifeKeeper hierarchy.
Shared disk resource. When you use LifeKeeper, shared storage
resources that are under LifeKeeper protection are reserved for use by
one server. This prevents inadvertent corruption of the data by other
servers in the cluster. When a server fails, the highest priority backup
server establishes ownership of the disk resources and locks out all other
servers.
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11
Active/Standby Scenario
Active/Standby Scenario
The configuration scenario in this section will describe the file movement
and the symbolic linking that takes place in a LifeKeeper-protected SAMS
environment from the creation of the resource hierarchy, to the extension of
that hierarchy to a backup server, to finally what occurs when the backup
server takes over after a switchover or failover.
Figure 2 Before the SAMS Hierarchy is Created
Shared
Server 1
Server 2
Storage
/etc/mail
/etc/md
/etc/mail
/etc/md
/var/md/store
/var/md/store
/var/spool/mqueue
/var/spool/mqueue
Configuration Notes:
1. The smiswitchgui and smserver packages are installed on both servers.
2. The same versions of the LifeKeeper Core, IP Recovery Kit and the
SAMS Recovery Kit are installed on both servers. The Core and
LifeKeeper GUI are initialized and made operational.
3. Because the SAMS resource instance requires a dependency on an
existing IP resource instance, a separate IP address must be obtained.
This IP address must be placed under LifeKeeper protection by creating
an IP resource instance on Server 1 and extending it to Server 2.
Note: Refer to the LifeKeeper IP Recovery Kit Administration Guide to
create the IP resource instance.
4. All SAMS configuration files (i.e. sendmail.cf, ms.conf) are configured
with the IP address that was LifeKeeper protected in Step 3. In particular,
keep in mind that you should provide the domain name that corresponds
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SAMS Recovery Kit Administration Guide
Active/Standby Scenario
to the switchable IP address when asked for the “Host Name” in the
Sendmail Switch installer program.
5. SAMS is tested to ensure that it will work properly on both servers using
equivalent configuration options on both servers.
6. The MTA and MSP spool directories (e.g., /var/spool/mqueue and
/var/spool/clientmqueue) or theirsubdirectories, if multiple mail queues
are being used, must be manually symbolically linked to a directory on a
shared file system. This shared file system does not have to be the same
as the shared file system that will be used by the other SAMS files. In
this example, all the SAMS configuration and data directories will be
located on the same shared file system. These will include:
/etc/mail
/etc/md
/var/md/store
Note: The manual process of symbolically linking the queue directories is
required on both Server 1 (primary) and Server 2 (backup).
Figure 3 During Creation of the SAMS Resource Hierarchy
Shared
Server 1
Server 2
Storage
/etc/mail
/etc/mail
/etc/mail
/etc/md
/etc/md
/etc/md
/var/md/store
/var/md/store
/var/md/store
mqueue
/var/spool/mqueue
/var/spool/mqueue*
* The symbolic link /var/spool/mqueue must be created manually.
The gray files and directories are symbolically linked to files on the
shared storage device.
LifeKeeper for Linux
13
Active/Standby Scenario
The black arrows represent active symbolic links (i.e. the files on Server
1 are actively linked to the shared storage device after the resource is
created).
Configuration Notes
During the creation of the SAMS resource instance on the primary server
(i.e. Server 1), the Recovery Kit moves the /etc/md, /etc/mail, and
/var/md/store to the shared file system. It then creates a symbolic link on the
local server (Server 1) to the file on the shared device.
IMPORTANT: If your specific SAMS configuration requires any other files
to be LifeKeeper-protected (or shared between the two servers), these files
must be manually moved to the shared file system and linked back to their
original location on each server after the creation of the SAMS resource
hierarchy.
Figure 4 During Extension of the SAMS Resource Hierarchy
Shared
Storage
Server 1
Server 2
/etc/mail
/etc/mail
etc/mail
etc/md
var/md/store
/etc/md
/etc/md
/var/md/store
/var/md/store
mqueue
/var/spool/mqueue*
/var/spool/mqueue*
* The symbolic link /var/spool/mqueue/ must be created manually.
The gray files and directories are symbolically linked to files on the
shared storage device.
The black arrows represent active symbolic links (i.e. the files on Server
1 are still actively linked to the shared storage device after the resource
is extended).
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SAMS Recovery Kit Administration Guide
Active/Standby Scenario
The gray arrows represent dangling links (i.e. the files on Server 2 are
linked to the shared storage device, but the shared device is not
mounted on Server 2. Therefore, the links on Server 2 are not active).
Configuration Notes
During the extension of the SAMS resource instance to the backup server
(i.e. Server 2), the Recovery Kit symbolically links the SAMS configuration
and data directories /etc/md, /etc/mail, and /var/md/store to the versions on
the shared file system. Note: The existing directories on Server 2 are saved
with a .LK extension.
IMPORTANT: If your specific SAMS configuration requires any other files
to be LifeKeeper-protected, these files must be manually moved to the shared
file system and linked back to their original locations on each server after the
extension of the SAMS resource hierarchy.
Figure 5 Switchover/Failover of the SAMS Hierarchy from
Server 1 to Server 2
Shared
Storage
Server 1
Server 2
/etc/mail
/etc/mail
etc/mail
etc/md
var/md/store
/etc/md
/etc/md
/var/md/store
/var/md/store
mqueue
/var/spool/mqueue*
/var/spool/mqueue*
* The symbolic link /var/spool/mqueue/ must be created manually.
The gray files and directories are symbolically linked to files on the
shared storage device.
The black arrows represent active symbolic links (i.e. the files on Server
2 are actively linked to the shared storage device after the resource is
switched or failed over).
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15
Active/Standby Scenario
The gray arrows represent dangling links (i.e. the files on Server 1 are
linked to the shared storage device, but the shared device is not
mounted on Server 1. Therefore, the links on Server 1 are not active).
Configuration Notes
When Server 2 becomes the active or primary server, the following occurs:
1. LifeKeeper unmounts the shared file system from Server 1 and mounts it
on Server 2. The dangling links on Server 2 now point to actual files.
2. Server 1 now contains the dangling links to the shared file system, since
the links from Server 2 now point to the files on the shared file system.
Administering SAMS Applications
After the SAMS applications are placed under LifeKeeper protection, the
SAMS administrator should use the LifeKeeper GUI for stopping and
starting SAMS. Since the configuration files and data files must exist on a
shared file system, administration of these files should be done on the shared
file system and not on the local file system.
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SAMS Recovery Kit Administration Guide
LifeKeeper Configuration Tasks
LifeKeeper Configuration Tasks
You can perform the following configuration tasks from the LifeKeeper GUI.
The following four tasks are described in this guide, as they are unique to a
SAMS resource instance, and different for each Recovery Kit.
•
•
•
•
hierarchy in your LifeKeeper cluster.
servers in your LifeKeeper cluster.
primary server to a backup server.
hierarchy from a single server in the LifeKeeper cluster.
The following tasks are described in the GUI Administration section within
the LifeKeeper Online Product Manual, because they are common tasks with
steps that are identical across all Recovery Kits.
•
Create a Resource Dependency. Creates a parent/child dependency
between an existing resource hierarchy and another resource instance and
propagates the dependency changes to all applicable servers in the
cluster.
•
Delete a Resource Dependency. Deletes a resource dependency and
propagates the dependency changes to all applicable servers in the
cluster.
•
•
In Service. Brings a resource hierarchy into service on a specific server.
Out of Service. Takes a resource hierarchy out of service on a specific
server.
•
View/Edit Properties. View or edit the properties of a resource
hierarchy on a specific server.
Note: Throughout the rest of this section, we explain how to configure your
Recovery Kit by selecting certain tasks from the Edit menu of the
LifeKeeper GUI. You can also select each configuration task from the
toolbar. You may also right click on a global resource in the Resource
Hierarchy Tree (left-hand pane) of the status display window to display the
LifeKeeper for Linux
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LifeKeeper Configuration Tasks
same drop down menu choices as the Edit menu. This, of course, is only an
option when a hierarchy already exists.
You can also right click on a resource instance in the Resource Hierarchy
Table (right-hand pane) of the status display window to perform all the
configuration tasks, except Creating a Resource Hierarchy, depending on the
state of the server and the particular resource.
Creating a SAMS Resource Hierarchy
IMPORTANT:
Before you create your SAMS resource hierarchy, several steps need to be
taken to ensure the proper functionality of the SAMS resource hierarchy
under LifeKeeper protection.
1. You must create a switchable IP address resource under LifeKeeper.
2. Sendmail Switch and Sendmail Advanced Message Server packages
should be installed on both servers. The installer program for both should
be run on each server. The answers provided to the installer program
should be the same on both servers. Also, when running the installer for
Sendmail Switch, the “Host Name” question should be answered with
the domain name that corresponds to the switchable IP address. After
installation is complete you should ensure that all of your configuration
files are configured for the existing protected IP resource.
3. The shared file system that is to be used for the SAMS data should be
mounted on the primary server.
4. The MTA and MSP spool directories (e.g., /var/spool/mqueue and
/var/spool/clientmqueue) or theirsubdirectories, if multiple mail queues
are being used, must be manually symbolically linked to the shared file
system from both servers.
5. It is also important to remember that LifeKeeper requires a working
communication path (i.e. heartbeat) before you can create your resource.
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SAMS Recovery Kit Administration Guide
LifeKeeper Configuration Tasks
To create a resource instance from the primary server, you should complete
the following steps:
1. From the LifeKeeper GUI menu, select Edit, then Resource. From the
drop down menu, select Create Resource Hierarchy.
IMPORTANT: The switchable IP address should be under LifeKeeper
protection before creating the SAMS resource instance.
A dialog box will appear with a drop down list box with all recognized
Recovery Kits installed within the cluster. Select SAMS from the drop
down listing.
SAMS
Click on the Next button to proceed to the next dialog box.
When the Back button is active in any of the dialog boxes, you can go
back to the previous dialog box. This is especially helpful should you
encounter an error that might require you to correct previously entered
information.
If you click the Cancel button at any time during the sequence of
creating your hierarchy, LifeKeeper will cancel the entire creation
process.
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19
LifeKeeper Configuration Tasks
2. Select the Switchback Type. This dictates how the SAMS instance will
be switched back to this server when it comes back into service after a
failover to the backup server. You can choose either intelligent or
automatic. Intelligent switchback requires administrative intervention to
switch the instance back to the primary/original server. Automatic
switchback means the switchback will occur as soon as the primary
server comes back on line and reestablishes LifeKeeper communication
paths.
The switchback type can be changed later, if desired, from the General
tab of the Resource Properties dialog box.
Click on the Next button to proceed to the next dialog box.
3. Select the Server where you want to create the SAMS resource
(typically this is referred to as the primary or template server). All the
servers in your cluster are included in the drop down list box.
Click on the Next button to proceed to the next dialog box.
4. Select the Shared File System.
IMPORTANT: This is a file system that will be used by the Recovery
Kit to copy the configuration and data directories. Click on the Next
button to proceed to the next dialog box.
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SAMS Recovery Kit Administration Guide
LifeKeeper Configuration Tasks
5. Select the IP Tag. This is a tag name given to the IP Resource hierarchy
that the SAMS resource will be dependent upon. The list will show only
those IP addresses that are in-service on this server.
Important: Verify that the priority of the IP Tag on the primary server is
higher than the priority of the IP Tag on the backup server.
Click on the Next button to proceed to the next dialog box.
6. Select or enter the Mail Tag. This is a tag name given to the SAMS
hierarchy. You can select the default, which is “sam” or enter your own
tag name.
sams
Click on the Next button to proceed to the next dialog box.
7. When you click on the Create button, the Create Resource Wizard will
create your SAMS resource.
8. At this point, LifeKeeper will check that there is a protected IP resource
available. It will also validate that you have provided valid data to create
your SAMS resource hierarchy. If LifeKeeper detects a problem, an
ERROR will appear in the information box. If the validation is
successful, your resource will be created. As part of the SAMS hierarchy
creation, the SAMS Recovery Kit moves the configuration and data
directories to the shared file system and links them to the original
location.
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21
LifeKeeper Configuration Tasks
Creating mail/sams resource…
BEGIN creation of resource “sams” on server “smokey”
at Fri Oct 12 10:31:34 EDT 2001
Creating Resource instance “sams with
id “sams” on server “smokey”
devicehier: Using
/opt/LifeKeeper/lkadm/subsys/scsi/device/bin/devicehier to construct
the hierarchy
.
.
.
END successful creation of resource “sams” on server “tigger”
at Fri Oct 12 10:32:19 EDT 2001
Click on the Next button to proceed to the next dialog box.
9. Another information box will appear explaining that you have
successfully created a SAMS resource hierarchy, and you must Extend
that hierarchy to another server in your cluster in order to place it under
LifeKeeper protection.
When you click on the Continue button, LifeKeeper will launch the
Pre-Extend Wizard that is explained later in this section.
If you click the Cancel button now, a dialog box will appear warning
you that you will need to come back and extend your SAMS resource
hierarchy to another server at some other time to put it under LifeKeeper
protection.
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SAMS Recovery Kit Administration Guide
LifeKeeper Configuration Tasks
10. Click the Done button to exit the Create Resource Hierarchy menu
selection.
Deleting a Resource Hierarchy
To delete a resource hierarchy from all the servers in your LifeKeeper
environment, complete the following steps:
1. From the LifeKeeper GUI menu, select Edit, then Resource. From the
drop down menu, select Delete Resource Hierarchy.
2. Select the name of the Target Server where you will be deleting your
SAMS resource hierarchy.
Note: If you selected the Delete Resource task by right-clicking from
the right pane on an individual resource instance, or from the left pane on
a global resource where the resource is on only one server this dialog box
will not appear.
Click on the Next button to proceed to the next dialog box.
3. Select the Hierarchy to Delete. Identify the resource hierarchy you wish
to delete, and highlight it.
Note: If you selected the Delete Resource task by right-clicking from
either the left pane on a global resource or the right pane on an individual
resource instance, this dialog will not appear.
LifeKeeper for Linux
23
LifeKeeper Configuration Tasks
sams
Click on the Next button to proceed to the next dialog box.
4. An information box appears confirming your selection of the target
server and the hierarchy you have selected to delete.
sams
Click on the Delete button to proceed to the next dialog box.
5. Another information box appears confirming that the SAMS resource
was deleted successfully.
Removing root resource hierarchy starting at “sams”:
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SAMS Recovery Kit Administration Guide
LifeKeeper Configuration Tasks
Important: The user must be careful when deleting the SAMS resource
hierarchy. The SAMS Recovery Kit keeps the backup server’s copy of
the configuration and data directories on the backup server itself. These
directories are moved to /etc and renamed with the extension .LK. When
the hierarchy is deleted, these .LK directories are renamed to their
original names on the backup server. On the primary server, the
configuration and data directories are copied from the shared file system
to their original locations and the SAMS daemons are left running.
6. Click the Done button to exit out of the Delete Resource Hierarchy menu
selection.
Extending Your Hierarchy
After you have created a hierarchy, you will want to extend that hierarchy to
another server in the cluster. There are three possible scenarios to extend
your resource instance from the template server to a target server. The first
scenario is when you “Continue” from creating the resource into extending
that resource to another server. The second scenario is when you enter the
Extend Resource Hierarchy task from the edit menu as shown below. The
third scenario is when you right click on an unextended hierarchy in either
the left or right hand pane. Each scenario takes you through the same dialog
boxes (with a few exceptions, which are clearly detailed below).
1. If you are entering the Extend wizard from the LifeKeeper GUI menu,
select Edit, then Resource. From the drop down menu, select Extend
Resource Hierarchy. This will launch the Extend Resource Hierarchy
wizard.
2. The first dialog box to appear will ask you to select the Template Server
where your SAMS resource hierarchy is currently in service. It is
important to remember that the Template Server you select now and the
Tag to Extend that you select in the next dialog box represent an in
service resource hierarchy. An error message will appear if you select a
resource tag that is not in service on the template server you selected.
The drop down box in this dialog provides the names of all the servers in
your cluster.
Note: If you are entering the Extend Resource Hierarchy task
immediately following the creation of a SAMS resource hierarchy, this
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dialog box will not appear, since the wizard has already identified the
template server in the create stage. This is also the case when you right-
click on either the SAMS resource icon in the left-hand pane or right-
click on the SAMS resource box in the right-hand pane the of the GUI
window and choose Extend Resource Hierarchy.
It should be noted that if you click the Cancel button at any time during
the sequence of extending your hierarchy, LifeKeeper will cancel the
extension process to that particular server and unextend any dependent
hierarchies. However, if you have already extended the resource to
another server, that instance will continue to be in effect until you
specifically unextend it.
Click on the Next button to proceed to the next dialog box.
3. Select the Tag to Extend. This is the name of the SAMS instance you
wish to extend from the template server to the target server. The wizard
will list in the drop down list box all the resources that you have created
on the template server, which you selected in the previous dialog box.
Note: Once again, if you are entering the Extend Resource Hierarchy
task immediately following the creation of a SAMS resource hierarchy,
this dialog box will not appear, since the wizard has already identified
the tag name of your SAMS resource in the create stage. This is also the
case when you right-click on either the SAMS resource icon in the left-
hand pane or on the SAMS resource box in the right-hand pane the of the
GUI window and choose Extend Resource Hierarchy.
sams
Click on the Next button to proceed to the next dialog box.
4. Select the Target Server where you are extending your SAMS resource
hierarchy. The drop down box provides the names of the servers in your
cluster that are not already in the selected hierarchy.
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Click on the Next button to proceed to the next dialog box.
5. Select the Switchback Type. This dictates how the SAMS instance will
be switched back to this server when it comes back into service after a
failover to the backup server. You can choose either intelligent or
automatic. Intelligent switchback requires administrative intervention to
switch the instance back to the primary/original server. Automatic
switchback means the switchback will occur as soon as the primary
server comes back on line and reestablishes LifeKeeper communication
paths.
The switchback type can be changed later, if desired, from the General
tab of the Resource Properties dialog box.
Click on the Next button to proceed to the next dialog box.
6. Select or enter the Target Priority of your extended SAMS resource.
The priority is a number between 1 and 999 indicating a server’s priority
in the cascading failover sequence for the resource. The hierarchy
priorities are sorted numerically, where a lower number means a higher
priority (the number 1 indicates the highest priority). Note that
LifeKeeper automatically assigns the number “1” to the server on which
the hierarchy is created. The priorities need not be consecutive, but no
two servers can have the same priority for a given resource.
Click on the Next button.
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7. An information box will appear explaining that LifeKeeper has
successfully checked your environment and that all the requirements for
extending this SAMS resource have been met. If there were some
requirements that had not been met, LifeKeeper would not allow you to
select the Next button, and the Back button would be enabled.
WARNING: SAMS is running on server “blueridge1”. Please stop
SAMS since the configuration files will be overwritten.
If you click on the Back button, you can make changes to your resource
extension according to any warning or error messages that may appear in
the information box.
If you click the Cancel button now, you will need to come back and
extend your SAMS resource hierarchy to another server at some other
time to put it under LifeKeeper protection.
Click on the Next button.
8. Select or enter the Mail Tag of your extended SAMS resource.
sams
When you click on the Extend button, LifeKeeper will launch you into
the Extend Resource configuration task.
9. This dialog box is for information purposes only. You cannot change the
IP Resource that appears in the box. Note: This dialog box will not
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appear if you are extending this SAMS resource immediately following
its creation.
Click on the Next button.
10. This dialog box is for information purposes only. You cannot change the
Netmask that appears in the box. Note: This dialog box will not appear
if you are extending this SAMS resource immediately following its
creation.
Click on the Next button.
11. Select or enter the Network Interface. Note: This dialog box will not
appear if you are extending this SAMS resource immediately following
its creation.
Click on the Next button.
12. Select a Backup Interface if you want to engage the IP Local Recovery
feature on the server that you are extending the IP resource. The default
value is none; however, if you have another network interface card
configured on this server, it should be listed in the drop down list.
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Click on the Next button to proceed to the next dialog box.
13. Select or enter the IP Resource Tag.
Click on the Next button.
14. An information box will appear verifying that the extension is being
Extending resource instances for sams
Creating dependencies
Setting switchback type for hierarchy
Creating equivalencies
LifeKeeper Admin Lock (sams) Released
Hierarchy successfully extended
Creating Resource Instance “sams” with
id “sams” on machine “blueridge1”:
Resource “sams” Successfully Created on machine “blueridge1”
Click the Next Server button if you want to extend the same SAMS
resource instance to another server in your cluster. This will repeat the
Extend Resource Hierarchy operation.
If you click the Finish button, LifeKeeper will verify that the extension
of the SAMS resource was completed successfully.
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15. Click the Done button in the last dialog box to exit from the Extend
Resource Hierarchy menu selection.
Note: Be sure to test the functionality of the new instance on both servers.
Unextending Your Hierarchy
1. From the LifeKeeper GUI menu, select Edit, then Resource. From the
drop down menu, select Unextend Resource Hierarchy.
2. Select the Target Server where you want to unextend the SAMS
resource. It cannot be the server where SAMS is currently in service.
Note: If you selected the Unextend task by right-clicking from the right
pane on an individual resource instance this dialog box will not appear.
Click on the Next button to proceed to the next dialog box.
3. Select the SAMS Hierarchy to Unextend.
Note: If you selected the Unextend task by right-clicking from either the
left pane on a global resource or the right pane on an individual resource
instance, this dialog will not appear.
sams
Click on the Next button to proceed to the next dialog box.
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4. An information box appears confirming the target server and the SAMS
resource hierarchy you have chosen to unextend.
sams
Click the Unextend button.
5. Another information box appears confirming that the SAMS resource
was unextended successfully.
Hierarchy Unextend Manager Initializing
Checking Target Machine Communications Path
LifeKeeper Admin Lock Flag (sams) Established
Removing Equivalencies
Removing Resources and Associated Dependencies
LifeKeeper Admin Lock Flag (sams) Released
Synchronizing LifeKeeper Databases
Unextend completed successfully
6. Click the Done button to exit out of the Unextend Resource Hierarchy
menu selection.
Testing Your Resource Hierarchy
You can test your SAMS resource hierarchy by initiating a manual
switchover. This will simulate a failover of a resource instance from the
primary server to the backup server.
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LifeKeeper Configuration Tasks
Performing a Manual Switchover from the GUI
You can initiate a manual switchover from the LifeKeeper GUI by selecting
Edit, then Resource, then finally In Service from the drop down menu. For
example, an in service request executed on a backup server causes the
application hierarchy to be placed in service on the backup server and taken
out of service on the primary server. At this point, the original backup server
is now the primary server and original primary server has now become the
backup server.
If you execute the Out of Service request, the application is taken out of
service without bringing it in service on the other server.
Recovery Operations
When the primary server fails, the SAMS Recovery Kit software performs
the following tasks:
•
Brings the switchable IP address into service on the backup server by
bringing in service a logical interface on one of that server’s physical
network interfaces
•
•
Mounts the file system(s) on the shared disk on that server
Starts the daemon processes related to SAMS
Since session context is lost following recovery, after the recovery, SMTP,
IMAP, and POP clients must reconnect using exactly the same procedures
they used to connect originally.
Note: During a LifeKeeper initiated switchover/failover and recovery of a
SAMS resource hierarchy, it is possible that mail sent to the protected
domains maybe temporarily deferred. The mail messages will be resent at
the next available interval following the application restore.
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Troubleshooting
Troubleshooting
This section provides a list of messages that you may encounter during the
process of creating, extending, removing and restoring a LifeKeeper SAMS
hierarchy, and, where appropriate, provides additional explanation of the
cause of the errors and necessary action to resolve the error condition. Other
messages from other LifeKeeper scripts and utilities are also possible. In
these cases, please refer to the documentation for the specific script or utility.
Messages in this section fall under these categories:
•
•
•
•
•
Hierarchy Creation Error Messages
ERROR: Must specify server name for hierarchy
The server name was not specified. Please enter a valid LifeKeeper
server name.
ERROR: Must specify tag name
The tag name was not specified. Please enter a valid tag name.
ERROR: Must specify IP tag name
An IP tag name must be specified. The SAMS hierarchy depends on the
IP resource for failover purposes.
ERROR: Must specify shared filesystem name
The name of the shared filesystem that SAMS is configured on must be
specified. Please enter the correct mount point name for the filesystem.
This shared filesystem is the location where all the configuration
directories are moved and linked to the original location.
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ERROR: Must specify Sendmail configuration file name
The name of the Sendmail configuration file must be specified. Enter the
correct name for the configuration file (/etc/mail/sendmail.cf).
Unknown error in script mailhier, err=$ERR
An unknown error has occurred in the script. See the LifeKeeper error
log for additional troubleshooting information.
ERROR: sendmail configuration file “$CONFIG” not found
The Sendmail configuration file that was specified was not found. Please
enter the correct information for the configuration file.
ERROR: sendmail mail store configuration file “$MS_CONF” not found
The mail store configuration file (/etc/md/store/ms.conf) was not found.
SAMS may not be installed or may be improperly installed.
ERROR: Mail queue directory setting invalid or not found in Sendmail
configuration file “$CONFIG”
The mail queue configuration cannot be determined. Please make sure
the mail queue configuration is correct. The mail queue directory(s)
should be defined in the Sendmail configuration file. LifeKeeper has
failed to find the queue directory option in the configuration file.
ERROR: Mail queue directory “$QUEUE_DIR” is not on a shared
filesystem
The mail queue directory(s) must be located on shared filesystems.
Please make sure your configuration is correct. The alternative option is
to create shared filesystems and link the mail queue directory(s) to these
shared filesystems. If a shared filesystem already exists, you may link
this directory to that shared filesystem.
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ERROR: Message store directory setting invalid or not found in mail store
configuration file “$MS_CONF”
The ms-path variable is missing or contains an incorrect value in the
/etc/md/store/ms.conf file.
ERROR: Failed to move “$DIR” to “$SHARED_FS”
LifeKeeper was unable to move a directory and its contents to the shared
file system.
ERROR: Failed to create sams resource instance
LifeKeeper was unable to create the SAMS resource. See the LifeKeeper
error log for additional troubleshooting information.
ERROR: Failed to create dependency between resources “$SAMS_TAG”
and “$CHILD_TAG”
LifeKeeper was unable to make the child resource (either a file system or
IP address) a dependency of the SAMS hierarchy. See the LifeKeeper
error log for additional troubleshooting information.
ERROR: Failed to create sams hierarchy:restore failed
LifeKeeper has created the SAMS resource hierarchy. However, the
SAMS daemons could not be started. Check your configuration and then
attempt to recreate the hierarchy. See the LifeKeeper error log for
additional troubleshooting information.
Unknown error in script sendmailins err=$ERR
An unknown error has occurred in the script. See the LifeKeeper error
log for additional troubleshooting information.
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ERROR: Failed to create LifeKeeper Application “mail” on server
“$SERVER”
LifeKeeper was unable to create the LifeKeeper application type “mail”
on the specified server. See the LifeKeeper error log for additional
troubleshooting information.
ERROR: Failed to create LifeKeeper “mail” Resource Type “sams” on
server “$SERVER”
LifeKeeper was unable to create the LifeKeeper resource type “sams” on
the specified server. See the LifeKeeper error log for additional
troubleshooting information.
ERROR: Failed to set state of resource “$TAG” on server “$SERVER”
LifeKeeper was unable to set the state for the specified SAMS resource.
See the LifeKeeper error log for additional troubleshooting information.
ERROR: Failed to set switchback type for resource “$TAG” on server
“$SERVER”
LifeKeeper was unable to set the switchback type for the specified
SAMS resource. See the LifeKeeper error log for additional
troubleshooting information.
ERROR: Failed to create resource “$TAG” on server “$SERVER”
LifeKeeper was unable to create the SAMS resource instance. See the
LifeKeeper error log for additional troubleshooting information.
Hierarchy Extend Error Messages
Error - canextend () - Unable to access template resource
“$TEMPLATE_TAG” on server “$TEMPLATE_SYSTEM”
LifeKeeper was not able to find the specified SAMS resource on the
template system.
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Troubleshooting
Error - canextend () - The “$DIR” directory does not exist on server
“$TARGET_SYSTEM”
The specified SAMS directory does not exist on the target system. Create
the directory on the target system and attempt to extend the SAMS
resource hierarchy again.
Error - canextend () – Failed to copy “$CONFIG_FILE_NAME” on server
“$TEMPLATE_SYSTEM” to “$NEW_CONFIG” on server
“$TARGET_SYSTEM”
LifeKeeper tried to copy the configuration file from the template system
to the target system.
Error - canextend () - Unable to find extendable child resources
The SAMS resource should have at least one shared filesystem and a
LifeKeeper-protected IP Address as resource dependencies. Verify that
the SAMS resource has these dependencies on the template system.
Error - canextend () - Unable to access resource information on server
“$TEMPLATE_SYSTEM”
This is probably due to an internal LifeKeeper error.
Error - canextend () - Unable to find template resource “$TAG”
This is probably due to an internal LifeKeeper error.
WARNING: mail queue directory “$QUEUE_DIR” is not a symbolic
link. Before bringing the SAMS hierarchy in service on server
“$TARGET_SYSTEM” you must ensure that this location is linked to
the same physical location as it is on server “$TEMPLATE_SYSTEM”.
This message indicates that one of the mail queue directories
(usually /var/spool/mqueue/…) is not linked to the shared filesystem.
The link must be created before SAMS is started on the target
system.
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Error - extend () - LifeKeeper Internal ID ($ID) is already being used by
another resource type on “$SERVER”
LifeKeeper uses an Internal Resource Identifier that must be unique for
all servers in a cluster. There is already a resource that has the same ID
as SAMS. Review all the resources that are LifeKeeper-protected on the
specified server.
Error - extend () - Failed to create resource instance on $SERVER
LifeKeeper creates a resource instance to represent the SAMS
application. The creation of the instance has failed.
Error - extend () -Failed to backup and link “$DIR” to “$SHARED_FS”
LifeKeeper was unable to copy a directory and/or create a symbolic link
between a directory and the shared file system. Please check the
permissions of the directory and the file system where LifeKeeper is
trying to establish the link.
Error - extend () - Failed to copy “$FILE” on server
“$TEMPLATE_SERVER” to “$NEW_FILE” on server
“$TARGET_SERVER”
LifeKeeper tried to copy a configuration file from the template system to
the target system. Verify the permissions of the files and directories
involved in the copy operation.
Bringing a SAMS Resource In-Service Error Messages
restore: sams: ERROR: No sams instance for tag “$TAG”
This error occurs when LifeKeeper tries to bring in-service a resource
that does not exist.
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restore: sams: ERROR: sendmail configuration file “$FILE” is empty
The Sendmail configuration is empty or does not exist.
restore: sams: SAMS is already running on $IP:$PORTLIST
This message is for informational purposes only. It indicates that the
SAMS daemons that are to be brought in-service are already running on
the specified IP address and ports.
restore: sams: ERROR: Unable to start the SAMS daemons
restore: sams: ERROR: Restore of sams resource “$TAG” failed.
restore: sams: ERROR: Please check the SAMS log files for error messages
LifeKeeper was unable bring the specified SAMS resource in-service.
The actual error message from the failed SAMS processes will appear in
the LifeKeeper error log.
Taking a SAMS Resource Out-of-Service Error
Messages
remove: sams: ERROR: No sams instance for tag “$TAG”
This message is found in the LifeKeeper log file. This error occurs when
LifeKeeper tries to bring a resource out-of-service, and it finds that the
Resource Tag does not exist.
remove: sams: ERROR: Unable to stop the SAMS daemons
remove: sams: ERROR: Removal of sams resource “$TAG” failed:
remove: sams: ERROR: <subprocess error message appears here>
remove: sams: ERROR: Please check the SAMS log files for error messages
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LifeKeeper was unable to stop the SAMS processes. The actual error
messages from subprocesses are displayed within this message. See the
LifeKeeper error log for additional troubleshooting information.
SAMS Resource Health Monitoring Error Messages
daemon is not responding on $IP:$PORT
quickCheck: sams: attempting local recovery of resource “$TAG”
These two messages indicate that one or more SAMS daemons are not
functioning properly and must be restarted by LifeKeeper.
SAMS Local Recovery Error Messages
Local Recovery: sams: instance “$ID”: ERROR: failed to restart daemons on
$IP:$PORTLIST
and
Local Recovery: sams: instance “$ID”: ERROR: failed to restart SAMS
These two error messages indicate that LifeKeeper has attempted
(unsuccessfully) to restart a failing SAMS resource. The actual error
messages from the SAMS processes appear in the LifeKeeper log. Since
the SAMS resource could not be recovered, the SAMS hierarchy must
now be failed over to a backup server.
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