No arp client available, skip send gratuitous ARP

[munin2k]

Hello,
I would like to refer again to the following request of mine:
https://github.com/cybertec-postgresql/vip-manager/issues/245

Unfortunately, I have not tested everything here. I have to agree with @sebastiangrill's last comment:

When a leader is changed, the new IP address is now assigned locally, but is not published on the network. This means that the system is not accessible for clients.

The system is only accessible via the VIP when I perform a manual arping.

Dec 27 11:40:23 scm-pgsql-01 vip-manager[961]: 2024/12/27 11:40:23 IP address 10.139.128.48/23 state is false, desired false
Dec 27 11:40:33 scm-pgsql-01 vip-manager[961]: 2024/12/27 11:40:33 IP address 10.139.128.48/23 state is false, desired false
Dec 27 11:40:43 scm-pgsql-01 vip-manager[961]: 2024/12/27 11:40:43 IP address 10.139.128.48/23 state is false, desired false
Dec 27 11:40:53 scm-pgsql-01 vip-manager[961]: 2024/12/27 11:40:53 current leader from DCS:
Dec 27 11:40:53 scm-pgsql-01 vip-manager[961]: 2024/12/27 11:40:53 current leader from DCS: scm-pgsql-01
Dec 27 11:40:53 scm-pgsql-01 vip-manager[961]: 2024/12/27 11:40:53 IP address 10.139.128.48/23 state is false, desired true
Dec 27 11:40:53 scm-pgsql-01 vip-manager[961]: 2024/12/27 11:40:53 Problems with producing the arp client: no IPv4 address available for interface
Dec 27 11:40:53 scm-pgsql-01 vip-manager[961]: 2024/12/27 11:40:53 Problems with producing the arp client: no IPv4 address available for interface
Dec 27 11:40:53 scm-pgsql-01 vip-manager[961]: 2024/12/27 11:40:53 Couldn't create an Arp client: no IPv4 address available for interface
Dec 27 11:40:53 scm-pgsql-01 vip-manager[961]: 2024/12/27 11:40:53 Configuring address 10.139.128.48/23 on ens224
Dec 27 11:40:53 scm-pgsql-01 vip-manager[961]: 2024/12/27 11:40:53 No arp client available, skip send gratuitous ARP
Dec 27 11:40:53 scm-pgsql-01 vip-manager[961]: 2024/12/27 11:40:53 IP address 10.139.128.48/23 state is true, desired true
Dec 27 11:40:53 scm-pgsql-01 vip-manager[961]: 2024/12/27 11:40:53 IP address 10.139.128.48/23 state is true, desired true
Dec 27 11:41:03 scm-pgsql-01 vip-manager[961]: 2024/12/27 11:41:03 IP address 10.139.128.48/23 state is true, desired true

We use vip-manager 2.8.0 from the pgdg repository.

I hope for help.
Thank you very much
André

[pashagolub]

Hello.

Please, do not hesitate to submit pull request that fixes this issue

[pashagolub]

@munin2k would you please check if #290 fixes your issues? Thanks in advance!

[munin2k]

@pashagolub:
I have built a package from the corresponding branch and installed it on the two Patroni nodes. During a switchover, the log output now looks inconspicuous and the VIP is also permanently accessible from the outside.

Jan 17 09:12:37 scm-pgsql-01 vip-manager[2633354]: 2025-01-17T09:12:37.610+0100        INFO        IP address 10.139.128.48/23 is down, must be down
Jan 17 09:12:47 scm-pgsql-01 vip-manager[2633354]: 2025-01-17T09:12:47.619+0100        INFO        IP address 10.139.128.48/23 is down, must be down
Jan 17 09:12:57 scm-pgsql-01 vip-manager[2633354]: 2025-01-17T09:12:57.628+0100        INFO        IP address 10.139.128.48/23 is down, must be down
Jan 17 09:13:05 scm-pgsql-01 vip-manager[2633354]: 2025-01-17T09:13:05.522+0100        INFO        Current leader from DCS:
Jan 17 09:13:05 scm-pgsql-01 vip-manager[2633354]: 2025-01-17T09:13:05.590+0100        INFO        Current leader from DCS: scm-pgsql-01
Jan 17 09:13:05 scm-pgsql-01 vip-manager[2633354]: 2025-01-17T09:13:05.590+0100        INFO        IP address 10.139.128.48/23 is down, must be up
Jan 17 09:13:05 scm-pgsql-01 vip-manager[2633354]: 2025-01-17T09:13:05.590+0100        INFO        Configuring address 10.139.128.48/23 on ens224
Jan 17 09:13:15 scm-pgsql-01 vip-manager[2633354]: 2025-01-17T09:13:15.604+0100        INFO        IP address 10.139.128.48/23 is up, must be up
Jan 17 09:13:25 scm-pgsql-01 vip-manager[2633354]: 2025-01-17T09:13:25.608+0100        INFO        IP address 10.139.128.48/23 is up, must be up

Many thanks for the quick implementation.