Re: postgres streaming replication for HA

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi Guys,

Even I have been trying to implement the automatic failover using a script in failover_command of pgpool-II

I've setup streaming replication using replication slots and 2 separate pgpool servers (primary and standby).
 
The postgresql failover works sometime and doesn't work sometimes. On further analysis it seem to be an issue with the systemctl utility in centos7 i.e., even when the postgres services are up and running fine, the systemctl shows the postgresql service in failed state and systemctl is not reliably starting/stopping/restarting the pstgresql service.

Any insight here on how to fix the issue and make the HA environment reliable would be highly appreciated. 


Thanks & Regards,
Sumeet Shukla


On Fri, Sep 8, 2017 at 12:37 PM, Sunil N Shinde <Sunil.Shinde@xxxxxxxxxx> wrote:

Hi Samed,

 

Thanks for the quick reply.

 

I am trying it manually with below step:

 

1.       Shut down the primary node

2.       Creating trigger file on standby node before  promoting it to primay.

3.       "recovery_target_timline='latest'”  adding this parameter in recovery file on standby and restarting it.

 

On current standby :

psql -p 5432 -c "select pg_is_in_recovery();"

pg_is_in_recovery

-------------------

t

(1 row)

 

 

But on Current Primary:

psql -c "select application_name, state, sync_priority, sync_state from pg_stat_replication;"

application_name | state | sync_priority | sync_state

------------------+-------+---------------+------------

(0 rows)

 

 

Thanks & Regards,
Sunil N Shinde

 

From: Samed YILDIRIM [mailto:samed@xxxxxxxxxx]
Sent: 08 September 2017 12:22
To: pgsql-admin@xxxxxxxxxxxxxx; Sunil N Shinde <Sunil.Shinde@xxxxxxxxxx>
Subject: Re: postgres streaming replication for HA

 

Hi Shinde,

 

Do you trying swithover manually? Or do you use any manager or script to handle switchover operation?

 

Best regards.


--
Yandex.Mail mobil uygulamasından gönderildi

08:51, 8 Eylül 2017, Sunil N Shinde <sunil.shinde@xxxxxxxxxx>:






 

 

Hi,

 

 

 

I am forming 2 node cluster of streaming replication for HA. I could able to succeed with the replication process.

 

But I am not able to complete the “switchover”.

 

 

 

Version : postgresql-9.6

 

OS :RHEL7

 

 

 

Master Node Parameters:

 

                                                wal_level = hot_standby 

 

                                                synchronous_commit = local

 

                                                archive_mode = on 

 

                                                archive_command = 'cp %p /var/lib/pgsql/9.6/data/archive/%f'                   

 

                                                max_wal_senders = 2

 

                                                wal_keep_segments = 10

 

                                                synchronous_standby_names = 'UWPGRECLUS2'

 

 

 

                                pb_hba.conf     

 

# Localhost

 

host    replication     replica          127.0.0.1/32            md5          

 

# PostgreSQL Master IP address

 

host    replication     replica          10.0.3.4/32            md5

 

# PostgreSQL SLave IP address

 

host    replication     replica          10.0.3.5/32            md5

 

 

 

Slave Node Parameters:

 

                                                wal_level = hot_standby 

 

                                                synchronous_commit = local

 

                                                max_wal_senders = 2

 

                                                wal_keep_segments = 10

 

                                                synchronous_standby_names = 'UWPGRECLUS2'

 

                                                hot_standby = on

 

 

 

 

Replication is properly happening from master to slave. But I am not able to switchover between the nodes.

 

 

 

Can anyone please guide me in this regard?

 

 

 

 

 

Thanks & Regards,


Sunil N Shinde


Assistant Manager – DBA


Mastek Ltd | Mastek Millennium Center, Millennium Business Park, Mahape, Navi Mumbai-400710 .


Mob:- 9819002393

 

 

 

 

 



[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]

  Powered by Linux