Re: Pgpool with high availability

After modifying the pgpool.conf configuration to correct a subnet mistake,  Previously, the wrong subnet was specified as /26, and it has now been corrected to /24. The configuration changes were as follows:

Previous Configuration:

delegate_ip = '10.127.1.18'

if_up_cmd = '/sbin/ip addr add $_IP_$/26 dev eth0 label eth0:1'

if_down_cmd = '/sbin/ip addr del $_IP_$/26 dev eth0'

arping_cmd = '/usr/sbin/arping -U $_IP_$ -w 1 -I eth0'

Updated Configuration:

delegate_ip = '10.127.1.18'

if_up_cmd = '/sbin/ip addr add $_IP_$/24 dev eth0 label eth0:1'

if_down_cmd = '/sbin/ip addr del $_IP_$/24 dev eth0'

arping_cmd = '/usr/sbin/arping -U $_IP_$ -w 1 -I eth0'

Current Issue:-

Following the subnet correction, the Virtual IP (VIP) 10.127.1.18 is now reachable only from the leader node (ha0002), while it remains unreachable from the standby nodes (ha0001 and ha0003). Below are the details of the connectivity status and the commands executed:

Leader Node (ha0002)

[root@staging-ha0002 PG_LOGS]# ping 10.127.1.18

PING 10.127.1.18 (10.127.1.18) 56(84) bytes of data.

64 bytes from 10.127.1.18: icmp_seq=1 ttl=64 time=0.041 ms

64 bytes from 10.127.1.18: icmp_seq=2 ttl=64 time=0.058 ms

64 bytes from 10.127.1.18: icmp_seq=3 ttl=64 time=0.060 ms

--- 10.127.1.18 ping statistics ---

3 packets transmitted, 3 received, 0% packet loss, time 2080ms

rtt min/avg/max/mdev = 0.041/0.053/0.060/0.008 ms

[root@staging-ha0002 PG_LOGS]# ping 10.127.1.18

PING 10.127.1.18 (10.127.1.18) 56(84) bytes of data.

64 bytes from 10.127.1.18: icmp_seq=1 ttl=64 time=0.041 ms

64 bytes from 10.127.1.18: icmp_seq=2 ttl=64 time=0.058 ms

64 bytes from 10.127.1.18: icmp_seq=3 ttl=64 time=0.060 ms

--- 10.127.1.18 ping statistics ---

3 packets transmitted, 3 received, 0% packet loss, time 2080ms

rtt min/avg/max/mdev = 0.041/0.053/0.060/0.008 ms

[pgbigboss@staging-ha0002 ~]$ pcp_watchdog_info -h 10.127.1.18 -p 9898 -U pgbigboss -W

Password:

3 3 YES ha0002:9999 Linux staging-ha0002 ha0002

ha0002:9999 Linux staging-ha0002 ha0002 9999 9000 4 LEADER 0 MEMBER

ha0001:9999 Linux staging-ha0001 ha0001 9999 9000 7 STANDBY 0 MEMBER

ha0003:9999 Linux staging-ha0003 ha0003 9999 9000 7 STANDBY 0 MEMBER

Standby Node (ha0001)

[root@staging-ha0001 ~]# ping 10.127.1.18

PING 10.127.1.18 (10.127.1.18) 56(84) bytes of data.

From 10.127.1.10 icmp_seq=1 Destination Host Unreachable

From 10.127.1.10 icmp_seq=2 Destination Host Unreachable

From 10.127.1.10 icmp_seq=3 Destination Host Unreachable

--- 10.127.1.18 ping statistics ---

5 packets transmitted, 0 received, +3 errors, 100% packet loss, time 4126ms

pipe 3

[pgbigboss@staging-ha0001 ~]$ pcp_watchdog_info -h 10.127.1.18 -p 9898 -U pgbigboss -W

Password:

ERROR: connection to host "10.127.1.18" failed with error "No route to host"

The VIP 10.127.1.18 is accessible from the leader node (ha0002) but not from the standby nodes (ha0001 and ha0003).

Thanks 

Vijay