6.7 Setting Up a Failover Group

6.7 Setting Up a Failover Group
Prev	Chapter 6 Failover Groups	Next

6.7.1 How to Configure a Primary Server
6.7.2 How to Add a Secondary Server
6.7.3 How to Synchronize Primary and Secondary Sun Ray Servers
6.7.4 How to Change the Group Manager Signature

Use the following procedures to set up a failover group.

Set up server addresses and client addresses. This step is needed only when using a private network or a when using a Sun Ray server that provides DHCP services. See Chapter 19, Alternate Network Configurations for details.
Configure a primary server.
Add secondary servers.
Synchronize the primary and secondary servers.
Change the Group Manager signature.

6.7.1 How to Configure a Primary Server

Layered administration of the failover group takes place on the primary server, where the master copy of the Sun Ray data store resides. The utreplica command designates a primary server, configures the server of its administration primary status, and configures the host names of all the secondary servers.

The term primary server reflects the replication relationship, not the failover order.

Before You Begin

Configure the primary server before you add the secondary servers.
If a common home directory is mounted on machines with different GNOME versions, conflicts between or among the versions cause unpredictable behavior. Do not try to use multiple GNOME versions with a common home directory.

Steps

Become superuser on the primary Sun Ray server.
If you did not initially configure the server as part of a failover group during the Sun Ray Software installation, you must configure it now using the utconfig command.
```
# /opt/SUNWut/sbin/utconfig
```
Answer y to this question:
```
Configure this server for a failover group? (y/[n])? y
          
```
You will also be asked for the group signature.
Configure this server as the primary Sun Ray server and identify all secondary servers.
```
# /opt/SUNWut/sbin/utreplica -p secondary-server1 [secondary-server2...]
```
where secondary_server1 [secondary_server2...] is a space-separated list of unique host names of the secondary servers.
When the script ends, a log file is available at:
For Oracle Solaris:
```
/var/adm/log/utreplica.Year_Month_Date_Hour:Minute:Second.log
```
For Oracle Linux:
```
/var/log/SUNWut/utreplica.Year_Month_Date_Hour:Minute:Second.log
```

6.7.2 How to Add a Secondary Server

The secondary servers in the group store a replicated version of the primary server's administration data.

Use the utreplica command to configure each secondary server of its secondary status and also the host name of the primary server for the group. Adding or removing secondary servers requires services to be restarted on the primary server.

If the secondary server has not been configured on the primary server, become superuser on the primary server and rerun the utreplica command with the new secondary server.
```
# /opt/SUNWut/sbin/utreplica -p -a secondary-server1 [secondary-server2...]
```
where secondary_server1 [secondary_server2...] is a space-separated list of unique host names of the secondary servers.
Become superuser on the secondary server.
If you did not initially configure the server as part of a failover group during the Sun Ray Software installation, you must configure it now using the utconfig command.
```
# /opt/SUNWut/sbin/utconfig
```
Answer y to this question:
```
Configure this server for a failover group? (y/[n])? y
          
```
You will also be asked for the group signature.
Add the secondary server.
```
# /opt/SUNWut/sbin/utreplica -s primary-server
```
where primary-server is the host name of the primary server.

6.7.3 How to Synchronize Primary and Secondary Sun Ray Servers

Log files for Sun Ray servers contain time-stamped error messages that can be difficult to interpret if the time is out of sync. To make troubleshooting easier, make sure that all secondary servers periodically synchronize with their primary server.

The Network Time Protocol (NTP) is the recommended protocol to synchronize primary and secondary servers. With NTP, you can synchronize to an absolute time source and it provides additional synchronization capabilities. In some deployments, the simpler TIME protocol configured through the rdate command may be sufficient.

Note

Both the NTP and TIME protocols are disabled by default on Oracle Solaris servers.

6.7.4 How to Change the Group Manager Signature

The utconfig command asks for a Group Manager signature if you chose to configure for failover. The signature, which is stored in the /etc/opt/SUNWut/gmSignature file, must be the same on all servers in the group.

The location can be changed in the gmSignatureFile property of the auth.props file.

To form a fully functional failover group, the signature file must meet the following criteria:

Owned by root with only root permissions.
Contain at least eight characters, in which at least two characters are letters and at least one character is not.

Note

For slightly better security, use long passwords.

Steps

Become superuser on the Sun Ray server.
Start the utgroupsig command.
```
# /opt/SUNWut/sbin/utgroupsig
```
You are prompted for the signature.
Enter the signature twice identically for acceptance.
For each Sun Ray server in the group, repeat this procedure.

Note

Be sure to use the utgroupsig command rather than any other method to provide the signature. utgroupsig also ensures proper internal replication.

Prev	Up	Next
6.6 Dedicated Primary Servers for Data Store	Home	6.8 Additional Failover Group Tasks