Hi Folks
we have a 1 master and 1 standby and 1 witness servers with EDB-EFM Cluster setups.
Master server automatically promoted to slave few days back.
Now we are plan maually promote to old stage like (OLD:- Master<-->slave ====>NOW TRY:- Slave--->Master.)
Please advice me how to do manual..donwtime is there arround 3hr+buffertime 1hr.
Please help me siva and team
Regards
Jithy
Hi,
It might be harder to get an answer because of "EFM" in the title, and EFM isn't related to how you set up replication. EFM is just a tool that can be used to monitor database clusters that are using streaming replication. I've asked our team to look at this question to answer your replication questions, but in the meantime can try to help a little. Feel free to ask replication questions with a different title and you might get a different set of people to help. :)
You have good links for some of the questions already. Here is some info on the others:
Cheers,
Bobby
Hi Jithesh,
Hope you are doing good.
Could you please provide some more info about your concern.
Actually Master server never promotes it self. Only SLAVE server can be able to promote.
Definition of Promote: Promoting is a small task to convert slave(read only) server to master(read+write) using pg_ctl promote command.
Command: ${pg_bin}/pg_ctl -D ${Data_directory} promote
Definition of Switchover: Switchover is a process of exchanging database server roles.
Ex: Slave becomes master and Master becomes slave after successful swichover.
Note: If you want to do just promote slave server to master(read+write) you can use efm command with promote tag. Or
If you want to do switchover (Exchaning roles), EFM it self will do this when you request -switchover tag with promote command. You can see same in 17 page of document "Performing Swichover".
EFM Documentation for v3.3 : https://get.enterprisedb.com/docs/EDB_Failover_Manager_Guide_v3.3.pdf
Hope this information helps, Or Please let us know if you still face any issues.
Regards
Siva.
Hi @sivamekala
Yes,this is good..i understanding many many thanks.
1.what is the differences between efm-replication and normal replication.(what internals of the these two)?
2. the command of scp in archive_command?
3.without scp also the data transferred successfully on slave side and synced.?
4.what is the differences in above both?
Regards
Jithy
Hi @Wallece_Jithy2,
Please refer answers to your queries:
1.what is the differences between efm-replication and normal replication.(what internals of the these two)?
- EFM does not have functionality to set up the replication, you need to set up the streaming replication which is built in feature in Postgres.
- The EFM document contains the steps to set up the streaming replication, EFM works only after you have set up the streaming replication.
2. the command of scp in archive_command?
- Using scp in archive_command, you can store the archives on other servers, i.e. to the standby server or the central backup server.
3.without scp also the data transferred successfully on slave side and synced.?
- Yes, the streaming replication uses the WAL sender and WAL receiver processes to do this. However, if due to heavy activity and large archive generation, standby goes out of sync and WAL receiver process breaks, it will not come up in sync, in that case, the restore_command from recovery.conf comes in picture.
- You can set up restore_command to apply the WAL archives from the archive location which you have set up using the archive_command.
4.what is the differences in above both?
- Answered above.
Please get back to us in case of any issues/queries.
Regards,
Sudhir
Hi @slonkar .,
Thanks for sharing this information,
1.what is active-passive and active -active.?
2.what is wal-based replication and xlog based replication.?
3.what is sycn and async(how to configure synchronous replication)?
>1.what is active-passive and active -active.?
Could you please elaborate on what active-passive and active -active you are referring to ?
>2.what is wal-based replication and xlog based replication.?
Kindly go through https://www.postgresql.org/docs/10/warm-standby.html
>3.what is sycn and async(how to configure synchronous replication)?
Kindly refer link https://www.postgresql.org/docs/10/warm-standby.html#SYNCHRONOUS-REPLICATION
1.what is active-passive and active -active.?
Could you please elaborate on what active-passive and active -active you are referring to ?
REPLICATIONS
2.What is HOT and WARM standby?
Hi,
It might be harder to get an answer because of "EFM" in the title, and EFM isn't related to how you set up replication. EFM is just a tool that can be used to monitor database clusters that are using streaming replication. I've asked our team to look at this question to answer your replication questions, but in the meantime can try to help a little. Feel free to ask replication questions with a different title and you might get a different set of people to help. :)
You have good links for some of the questions already. Here is some info on the others:
Cheers,
Bobby
@sivamekala wrote:
Definition of Promote: Promoting is a small task to convert slave(read only) server to master(read+write) using pg_ctl promote command.
Command: ${pg_bin}/pg_ctl -D ${Data_directory} promote
Or by creating the trigger file specified in recovery.conf. EFM, for example, creates a trigger file rather than using pg_ctl to promote a standby.
Cheers,
Bobby