Re: [ADMIN] High Availability: Hot Standby vs. Warm Standby

2010-07-13 Thread Thomas Kellerer
Greg Smith, 12.07.2010 18:11: Yes, but if you try you'll discover that actually getting any shared disk or file system replication solution setup so that you really do achieve less failover loss than the file shipping approach will be expensive, complicated, fragile in its own way, and just

Re: [ADMIN] High Availability: Hot Standby vs. Warm Standby

2010-07-12 Thread Thomas Kellerer
Greg Smith, 10.07.2010 14:44: Is there a difference in how much data could potentially be lost in case of a failover? E.g. because 9.0 replicates the changes quicker than 8.4? There's nothing that 9.0 does that you can' t do with 8.4 and the right software to aggressively ship partial files

Re: [ADMIN] High Availability: Hot Standby vs. Warm Standby

2010-07-12 Thread Brad Nicholson
On Mon, 2010-07-12 at 08:58 +0200, Thomas Kellerer wrote: Greg Smith, 10.07.2010 14:44: Is there a difference in how much data could potentially be lost in case of a failover? E.g. because 9.0 replicates the changes quicker than 8.4? There's nothing that 9.0 does that you can' t do

Re: [ADMIN] High Availability: Hot Standby vs. Warm Standby

2010-07-12 Thread Greg Smith
Thomas Kellerer wrote: The manual lists three possible solutions to HA: shared disk failover, file system replication and Warm/Hot Standby. I'm not an admin (nor a DBA), so my question might sound a bit stupid: from my point of view solutions using shared disk failover of file system

Re: [ADMIN] High Availability: Hot Standby vs. Warm Standby

2010-07-12 Thread Greg Smith
Brad Nicholson wrote: One further thing to mention - all of these solutions are based on making the physical blocks available (actually, I'm not sure about Streaming replication in 9.0). You're right here; the SR feature in 9.0 is essentially near real-time partial WAL file shipping, and the

Re: [ADMIN] High Availability: Hot Standby vs. Warm Standby

2010-07-10 Thread Greg Smith
Thomas Kellerer wrote: I'm wondering about the differences when the failover situation occurs. From reading the docs, I get the impression that 9.0's streaming replication might be faster than 8.4's WAL shipping, but otherwise offers the same level of data protection. Is there a difference in

[ADMIN] High Availability: Hot Standby vs. Warm Standby

2010-07-09 Thread Thomas Kellerer
Hi, we are contemplating the possibilities for a Postgres HA installation. As the rollout is targeted towards the end of the year, 9.0 and it's new features might be an option for us. Now from a HA point of view, what is the major difference between 9.0's Hot Standby and 8.x's Warm Standby?

Re: [ADMIN] High Availability: Hot Standby vs. Warm Standby

2010-07-09 Thread Rob Wultsch
On Fri, Jul 9, 2010 at 4:51 AM, Thomas Kellerer spam_ea...@gmx.net wrote: Hi, we are contemplating the possibilities for a Postgres HA installation. As the rollout is targeted towards the end of the year, 9.0 and it's new features might be an option for us. Now from a HA point of view,

Re: [ADMIN] High Availability: Hot Standby vs. Warm Standby

2010-07-09 Thread Thomas Kellerer
Hi, Rob Wultsch wrote on 09.07.2010 18:14: I am aware that I can use the 9.0 standby server for read only queries, but that is (currently) not something we need Taking SQL backups without impacting the master might be something to consider. Interesting point. Thanks for mentioning that.

Re: [ADMIN] High Availability: Hot Standby vs. Warm Standby

2010-07-09 Thread Kevin Grittner
Thomas Kellerer spam_ea...@gmx.net wrote: So my assumption is correct that streaming replication does mean that in case of a failover less transactions are lost? Yes, that is correct. -Kevin -- Sent via pgsql-admin mailing list (pgsql-admin@postgresql.org) To make changes to your

Re: [ADMIN] High Availability: Hot Standby vs. Warm Standby

2010-07-09 Thread Brad Nicholson
On Fri, 2010-07-09 at 18:31 +0200, Thomas Kellerer wrote: Hi, Rob Wultsch wrote on 09.07.2010 18:14: I am aware that I can use the 9.0 standby server for read only queries, but that is (currently) not something we need Taking SQL backups without impacting the master might be

Re: [ADMIN] High Availability: Hot Standby vs. Warm Standby

2010-07-09 Thread Kasia Tuszynska
, 2010 10:19 AM To: Thomas Kellerer Cc: pgsql-admin@postgresql.org Subject: Re: [ADMIN] High Availability: Hot Standby vs. Warm Standby On Fri, 2010-07-09 at 18:31 +0200, Thomas Kellerer wrote: Hi, Rob Wultsch wrote on 09.07.2010 18:14: I am aware that I can use the 9.0 standby server for read

Re: [ADMIN] High Availability: Hot Standby vs. Warm Standby

2010-07-09 Thread Brad Nicholson
] On Behalf Of Brad Nicholson Sent: Friday, July 09, 2010 10:19 AM To: Thomas Kellerer Cc: pgsql-admin@postgresql.org Subject: Re: [ADMIN] High Availability: Hot Standby vs. Warm Standby On Fri, 2010-07-09 at 18:31 +0200, Thomas Kellerer wrote: Hi, Rob Wultsch wrote on 09.07.2010 18:14