Re: [GENERAL] Shared WAL archive between master and standby: WALs not always identical

2017-02-28 Thread Sasa Vilic
On 2017-02-28 16:57, Jon Nelson wrote: What does pg_xlogdump say about the differences in the files? What a nice tool. I didn't realize that it exists for 9.6. Unfortunately, we gave up on shared WAL archive, so I don't if I will still have all both WALs. I have one conflicting WAL from one o

Re: [GENERAL] Shared WAL archive between master and standby: WALs not always identical

2017-02-28 Thread Sasa Vilic
On 2017-02-28 16:41, Adrian Klaver wrote: Seems to mean the simpler thing to do would be to set standby to archive_mode = on, in which case the standby would not contribute WAL's until it was promoted which would seem to be what you want. Yes, that was my first thought. Except that documentatio

Re: [GENERAL] Shared WAL archive between master and standby: WALs not always identical

2017-02-27 Thread Sasa Vilic
On 2017-02-28 06:14, Adrian Klaver wrote: On 02/27/2017 05:52 PM, Sasa Vilic wrote: Because standby is running in syncronous replication, whereby wal archiver is asynchronous. Therefore there is a small window where slave has received the data but master has not pushed it yet to wal archive

Re: [GENERAL] Shared WAL archive between master and standby: WALs not always identical

2017-02-27 Thread Sasa Vilic
Am 28.02.2017 02:50 schrieb "David G. Johnston" : It is customary to inline or bottom-posts on these lists. Please follow the example of those responding to your emails. On Mon, Feb 27, 2017 at 6:45 PM, Sasa Vilic wrote: > And also this: > > """ > If archi

Re: [GENERAL] Shared WAL archive between master and standby: WALs not always identical

2017-02-27 Thread Sasa Vilic
2017 05:29 PM, Sasa Vilic wrote: > >> Master is streaming directly to standby. Both master and standby are >> pushing WALs to archive. >> >> My point is that in case that master crashed completely (and we failover >> to standby) and wal archiver on master didn'

Re: [GENERAL] Shared WAL archive between master and standby: WALs not always identical

2017-02-27 Thread Sasa Vilic
ment). Of course, the next WAL segment will be sent by new master, but we are going to miss exactly this one WAL segment during which failover occurred and thus introduce interruption in our WAL stream. Am I right? Regards, Sasa On 28 February 2017 at 02:33, Sasa Vilic wrote: > Hi David, > >

Re: [GENERAL] Shared WAL archive between master and standby: WALs not always identical

2017-02-27 Thread Sasa Vilic
10, David G. Johnston wrote: > On Mon, Feb 27, 2017 at 5:40 PM, Sasa Vilic wrote: > >> Aren't WALs from master and standby supposed to be identical? >> > > ​This would seem unwise to assume on its face and at least one piece of > documentation directly mentions th

Re: [GENERAL] Shared WAL archive between master and standby: WALs not always identical

2017-02-27 Thread Sasa Vilic
slave. Therefore there is no interruption in WAL stream. Regards, Sasa On 28 February 2017 at 01:57, Adrian Klaver wrote: > On 02/27/2017 04:40 PM, Sasa Vilic wrote: > >> Hallo, >> >> I am trying to setup shared WAL archive between master and standby. >> Standby is synchrono

[GENERAL] Shared WAL archive between master and standby: WALs not always identical

2017-02-27 Thread Sasa Vilic
Hallo, I am trying to setup shared WAL archive between master and standby. Standby is synchronously streaming from master and both servers run with archive_mode = always. The ideas is that when promoting standby to master we would not missed WALs. My problem is that sometimes WAL uploaded from ma