How to restore Wall IP when in non-cluster mode

Answer

There are times when one of the hosts is down and you need to bring the system to non-cluster mode and make it operational for the users to use. But for the system to be operational, the wall IP must be accessible.

1. Find the details of the wall IP being used

Refer to Technotes # 1681985

- How to find the wall IP and/or VIP addresses of PDA/Netezza

Using either method, you can look for the wall IP information:

# grep wall /var/lib/heartbeat/crm/cib.xml
<primitive class="ocf" id="wall_ip" provider="heartbeat" type="IPaddr">
<instance_attributes id="wall_ip_ext_config">
<nvpair id="wall_ip_ext_attr_1" name="ip" value="172.168.16.74"/>
<nvpair id="wall_ip_ext_attr_2" name="netmask" value="26"/>
<nvpair id="wall_ip_ext_attr_3" name="nic" value="eth6"/>

# /usr/sbin/cibadmin –Q > /tmp/cib_backup.xml
# grep wall /tmp/cib_backup.xml
<primitive class="ocf" id="wall_ip" provider="heartbeat" type="IPaddr">
<instance_attributes id="wall_ip_ext_config">
<nvpair id="wall_ip_ext_attr_1" name="ip" value="172.168.16.74"/>
<nvpair id="wall_ip_ext_attr_2" name="netmask" value="26"/>
<nvpair id="wall_ip_ext_attr_3" name="nic" value="eth6"/>

Both output showed us that the wall IP address/netmask is 172.168.16.74/26 and the interface is eth6

# ping 172.168.16.74

# ifconfig eth6:0 172.168.16.74 netmask 255.255.255.192 up

Notes:

- In IP subnetting, the bit mask (26) translates to netmask, 255.255.255.192

- For best practice, use logical interface #0 for the physical interface (eth6)

# ifconfig eth6:0

# ping 172.168.16.74