missing client_hostname

Started by Atul Kumarover 2 years ago6 messagesgeneral
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#1Atul Kumar
akumar14871@gmail.com

Hi,

I have postgres 12 running in centos7.

I recently have configured streaming replication from master to standby
using below command:

/usr/bin/pg_basebackup -h <master ip> -p 5432 -U replication -D
/path/of/data/directory/ -Fp -R -Xs -P -c fast

It was successfully configured but when I query pg_stat_replication I don't
get the hostname in output:

postgres=# select * from pg_stat_Replication;
-[ RECORD 1 ]----+------------------------------
pid | 3692075
usesysid | 16384
usename | replication
application_name | walreceiver
client_addr | slave_ip
*client_hostname* |
client_port | 52500
backend_start | 2023-11-01 08:26:45.373297-07
backend_xmin |
state | streaming
sent_lsn | 2E5/400001C0
write_lsn | 2E5/400001C0
flush_lsn | 2E5/400001C0
replay_lsn | 2E5/400001C0
write_lag |
flush_lag |
replay_lag |
sync_priority | 0
sync_state | async
reply_time | 2023-11-01 08:41:47.60122-07

So please help me understand the reason for this and how I will fix this
issue of having a respective hostname in this catalog.

Regards,
Atul

#2Christoph Moench-Tegeder
cmt@burggraben.net
In reply to: Atul Kumar (#1)
Re: missing client_hostname

## Atul Kumar (akumar14871@gmail.com):

It was successfully configured but when I query pg_stat_replication I don't
get the hostname in output:

I Recommend The Fine Manual:
https://www.postgresql.org/docs/current/monitoring-stats.html#MONITORING-PG-STAT-REPLICATION-VIEW
"... and only when log_hostname is enabled".

Regards,
Christoph

--
Spare Space

#3Atul Kumar
akumar14871@gmail.com
In reply to: Christoph Moench-Tegeder (#2)
Re: missing client_hostname

I have already enabled log_hostname, still *client_hostname is not showing
up.*

Do you think that just because I use ip instead of hostname while using
pg_basebackup could be the reason for it ?

Regards,
Atul

On Wed, Nov 1, 2023 at 11:23 PM Christoph Moench-Tegeder <cmt@burggraben.net>
wrote:

Show quoted text

## Atul Kumar (akumar14871@gmail.com):

It was successfully configured but when I query pg_stat_replication I

don't

get the hostname in output:

I Recommend The Fine Manual:

https://www.postgresql.org/docs/current/monitoring-stats.html#MONITORING-PG-STAT-REPLICATION-VIEW
"... and only when log_hostname is enabled".

Regards,
Christoph

--
Spare Space

#4Mateusz Henicz
mateuszhenicz@gmail.com
In reply to: Atul Kumar (#3)
Re: missing client_hostname

Did you reconnect your replica after enabling log_hostname? If not, then do
it and check again.

śr., 1 lis 2023, 19:03 użytkownik Atul Kumar <akumar14871@gmail.com>
napisał:

Show quoted text

I have already enabled log_hostname, still *client_hostname is not
showing up.*

Do you think that just because I use ip instead of hostname while using
pg_basebackup could be the reason for it ?

Regards,
Atul

On Wed, Nov 1, 2023 at 11:23 PM Christoph Moench-Tegeder <
cmt@burggraben.net> wrote:

## Atul Kumar (akumar14871@gmail.com):

It was successfully configured but when I query pg_stat_replication I

don't

get the hostname in output:

I Recommend The Fine Manual:

https://www.postgresql.org/docs/current/monitoring-stats.html#MONITORING-PG-STAT-REPLICATION-VIEW
"... and only when log_hostname is enabled".

Regards,
Christoph

--
Spare Space

#5Atul Kumar
akumar14871@gmail.com
In reply to: Mateusz Henicz (#4)
Re: missing client_hostname

Yes, I have already tried that as log_hostname was already enabled by me.

By the way, just to inform you that the log_hostname is used for logging
the hostname instead of ip addresses in error log files only, Please
correct me if I am wrong.

Could you help me in telling my query that Iasked in my trial mail:

"Do you think that just because I use ip_address instead of hostname while
using pg_basebackup on standby side could be the reason for not showing
client_hostname in pg_stat_replication ?" I used below command in standby
node:

/usr/bin/pg_basebackup -h <master ip> -p 5432 -U replication -D
/path/of/data/directory/ -Fp -R -Xs -P -c fast

Regards.

On Wed, Nov 1, 2023 at 11:46 PM Mateusz Henicz <mateuszhenicz@gmail.com>
wrote:

Show quoted text

Did you reconnect your replica after enabling log_hostname? If not, then
do it and check again.

śr., 1 lis 2023, 19:03 użytkownik Atul Kumar <akumar14871@gmail.com>
napisał:

I have already enabled log_hostname, still *client_hostname is not
showing up.*

Do you think that just because I use ip instead of hostname while using
pg_basebackup could be the reason for it ?

Regards,
Atul

On Wed, Nov 1, 2023 at 11:23 PM Christoph Moench-Tegeder <
cmt@burggraben.net> wrote:

## Atul Kumar (akumar14871@gmail.com):

It was successfully configured but when I query pg_stat_replication I

don't

get the hostname in output:

I Recommend The Fine Manual:

https://www.postgresql.org/docs/current/monitoring-stats.html#MONITORING-PG-STAT-REPLICATION-VIEW
"... and only when log_hostname is enabled".

Regards,
Christoph

--
Spare Space

#6Christoph Moench-Tegeder
cmt@burggraben.net
In reply to: Atul Kumar (#3)
Re: missing client_hostname

Hi,

please don't top-post.

## Atul Kumar (akumar14871@gmail.com):

I have already enabled log_hostname, still *client_hostname is not showing
up.*

It's always helpful to mention relevant non-default settings along
with the question. Was log_hostname really active at backup start
time? (Check pg_settings before starting the backup). Can the server
actually resolve the IP address to a host name?

Do you think that just because I use ip instead of hostname while using
pg_basebackup could be the reason for it ?

No.

Regards,
Christoph

--
Spare Space