Re: Can master and slave on different PG versions?

David,

So initially i have physical replication configured, so to upgrade slave to
9.6 version i did converted master slave to logical replication and then
try to upgrade the slave to 9.6. I am getting this error when i try to
start the slave. Any idea?

2017-11-08 05:08:49 UTC [20063]: [1-1] user= db= host= LOG: shutting down
2017-11-08 05:08:49 UTC [20063]: [2-1] user= db= host= LOG: database
system is shut down
2017-11-08 05:09:45 UTC [20322]: [1-1] user= db= host= LOG: database
system was shut down at 2017-11-08 05:08:55 UTC
2017-11-08 05:09:45 UTC [20322]: [2-1] user= db= host= LOG: entering
standby mode
2017-11-08 05:09:45 UTC [20322]: [3-1] user= db= host= WARNING: WAL was
generated with wal_level=minimal, data may be missing
2017-11-08 05:09:45 UTC [20322]: [4-1] user= db= host= HINT: This happens
if you temporarily set wal_level=minimal without taking a new base backup.
2017-11-08 05:09:45 UTC [20322]: [5-1] user= db= host= FATAL: hot standby
is not possible because wal_level was not set to "replica" or higher on the
master server
2017-11-08 05:09:45 UTC [20322]: [6-1] user= db= host= HINT: Either set
wal_level to "replica" on the master, or turn off hot_standby here.
2017-11-08 05:09:45 UTC [20312]: [3-1] user= db= host= LOG: startup
process (PID 20322) exited with exit code 1
2017-11-08 05:09:45 UTC [20312]: [4-1] user= db= host= LOG: aborting
startup due to startup process failure
2017-11-08 05:09:45 UTC [20312]: [5-1] user= db= host= LOG: database
system is shut down

Thanks,
Ram

On Mon, Oct 9, 2017 at 4:15 PM, David G. Johnston <
david(dot)g(dot)johnston(at)gmail(dot)com> wrote:

> On Mon, Oct 9, 2017 at 4:06 PM, rammohan ganapavarapu <
> rammohanganap(at)gmail(dot)com> wrote:
>
>> Hi,
>>
>> Is it possible to add 9.6 version Slave to 9.4 master?
>>
>>
> ​Physical replication, no; Logical replication, yes - if the software you
> are using is compatible with both versions.
>
> David J.​
>