Follow these steps to create and configure a remote stand-alone
secondary (RSS) server that synchronizes with a primary server.
Before you begin
Ensure that these prerequisites are in place:
- The RSS server must be created on a separate machine that has
the same operating system (OS) platform with the primary server accessible
over the local area network (LAN).
- On the RSS server, make sure that all chunk paths are created
and have the correct permissions, and ensure that there is enough
space on the disks to hold all the data. The RSS server must have
the same partition path as on the primary server to hold the Informix
chunkfiles.
- If you are not using NIS, set up ccm_root and
Informix users and group on the RSS server. Use the same numeric user
and group IDs as on the primary server.
Procedure
- Ensure that the primary server and the RSS server can connect
to each other.
These two servers must be configured
to use a DNS server.
- Determine the name of the primary server.
For
example, hawk1.
The RSS server name is derived
from the primary server name by prefixing rss_ to
it.
For example, rss_hawk1.
Update
the /etc/services file (or its NIS equivalent)
on the host for the primary server to include an entry for RSS. The
host for the RSS server must have two entries. One for the primary
and the other of the RSS server. Doing so contains the entries of
both the primary and RSS servers and would look like:
The services
entry for the database server has the following syntax:
PrimaryServerName_PrimaryServerHostName unique_informix_port/tcp
rss_PrimarySeverName_SecondaryServerHostName unique_informix_port/tcp
For
example:
hawk1_sol1 8100/tcp
rss_hawk1_sol2 8101/tcp
- Set up the trusted environment by creating the /etc/hosts.equiv file.
That is, you can use the rcp and rsh commands
without entering a password for both ccm_root and
Informix users between the primary and RSS server.
For
detailed steps, see Setting Up the Trusted Environment and The hosts.equiv file in the help for IBM® Informix®.
- If the primary server and the RSS server do not share $CCM_HOME,
do the following steps:
- Add the RSS server entry to the file $CCM_HOME/informix/etc/sqlhosts,
which is on the primary server.
The server entry for
the database server has the following syntax:
servername onipcshm serverhostname servername
servername_net onsoctcp serverhostname servername_serverhostname
For
example, if the RSS server host name is
sol2 and
the RSS server name is
rss_hawk1, then the server
entry would be:
rss_hawk1 onipcshm sol2 rss_hawk1
rss_hawk1_net onsoctcp sol2 rss_hawk1_sol2
- Add the primary server entry to the file $CCM_HOME/informix/etc/sqlhosts,
which is on the RSS server.
This file is only present
if you have configured IBM Rational® Synergy using
the ccm_install command.
Initially, this
file on the RSS server host is empty. Update this file to contain
the primary server entry.
For example, if the primary server
name is
hawk1 and the primary server host name
is
sol1, then the server entry must be:
hawk1 onipcshm sol1 hawk1
hawk1_net onsoctcp sol1 hawk1_sol1
- Create a directory on the file system.
For example, /vol/shared/export_dir.
This
directory must be accessible by both the primary and RSS servers,
which is usually on the NFS mounted file system.
This directory
must be owned by user informix and must belong
to the group informix.
Create the directory
as follows:
# cd /vol/shared
# mkdir export_dir
# chown informix:informix export_dir
- Shutdown all Synergy databases on the primary server and
verify that all users have exited by using the ccm monitor command.
# su - ccm_root
$ CCM_HOME=/usr/local/ccm721 # Adjust as appropriate
$ PATH=$CCM_HOME/bin:$PATH
$ export CCM_HOME PATH
$ ccmdb shutdown <dbpath> # Repeat per database
$ ccm monitor
- Use the ccmsrv rss_export command to
export the data on the primary server for creating the RSS server.
For example:
# su informix
$ ccmsrv rss_export -t /vol/shared/export_dir -s hawk1
- Use the ccmsrv rss_create command to
create an RSS server on the RSS server host.
For example:
# su informix
$ ccmsrv rss_create -f /vol/shared/export_dir -p hawk1
- After the installation, add the ccmsrv online command
to the startup scripts of the RSS server. On server reboot, the Informix
server on the RSS host needs to be online.
- Do a backup using the RSS server.
You must have an NFS mount to the database path from the RSS
server with rw options. There is no command line
option for using the RSS server. The ccmdb backup command
automatically chooses to use the secondary server to do a backup when
the command is running on the RSS server machine.
- Drop the RSS server:
- Use the ccmsrv rss_drop command on the primary
server to remove the identity of the RSS server. For example:
# su informix
$ ccmsrv rss_drop -s hawk1
- Bring both the primary and secondary database servers offline.
- In the onconfig file on the primary server,
make the following changes:
- Replace LOG_INDEX_BUILDS 1 with LOG_INDEX_BUILDS
- Replace ARCHIVEDEV <old archive path> with ARCHIVEDEV
/dev/null
- Clean up the export directory that was created in step 5.
- On the secondary server, clean up the Informix chunk files, and
clean up the $CCM_HOME runarea if the primary server
and the RSS server do not share $CCM_HOME.
- Bring the database server online in the primary server.