RE: Multiple hosts in connection string failed to failover in non-hot standby mode - Mailing list pgsql-hackers

From tsunakawa.takay@fujitsu.com
Subject RE: Multiple hosts in connection string failed to failover in non-hot standby mode
Date
Msg-id TYAPR01MB299012CAC510D2644AEC2246FE160@TYAPR01MB2990.jpnprd01.prod.outlook.com
Whole thread Raw
In response to Multiple hosts in connection string failed to failover in non-hot standby mode  (Hubert Zhang <zhubert@vmware.com>)
Responses Re: Multiple hosts in connection string failed to failover in non-hot standby mode
List pgsql-hackers
Please send emails in text format.  Your email was in HTML, and I changed this reply to text format.


From: Hubert Zhang <zhubert@vmware.com>
> Libpq has supported to specify multiple hosts in connection string and enable auto failover when the previous
PostgreSQLinstance cannot be accessed. 
> But when I tried to enable this feature for a non-hot standby, it cannot do the failover with the following messages.
>
> psql: error: could not connect to server: FATAL:  the database system is starting up

Was the primary running and accepting connections when you encountered this error?  That is, if you specified
host="host1host2", host1 was the non-hot standby and host2 was a running primary?  Or only the non-hot standby was
running?

If a primary was running, I'd say it's a bug...  Perhaps the following part in libpq gives up connection attempts wen
theabove FATAL error is returned from the server.  Maybe libpq should differentiate errors using SQLSTATE and continue
connectionattempts on other hosts. 

[fe-connect.c]
                /* Handle errors. */
                if (beresp == 'E')
                {
                    if (PG_PROTOCOL_MAJOR(conn->pversion) >= 3)
...
#endif

                    goto error_return;
                }

                /* It is an authentication request. */
                conn->auth_req_received = true;

                /* Get the type of request. */


Regards
Takayuki Tsunakawa




pgsql-hackers by date:

Previous
From: Heikki Linnakangas
Date:
Subject: Re: Question about make coverage-html
Next
From: Arseny Sher
Date:
Subject: Use-after-free in 12- EventTriggerAlterTableEnd