Transactional Replication and WAN links

re: Transactional Replication and WAN links

Robert L Davis — Tue, 31 May 2011 20:40:50 GMT

Which WAN accelerator are you using? We use Bedrock and just recently got it installed into our datacenters. I don't have metric yet on how it has affected replication.

re: Transactional Replication and WAN links

Argenis — Tue, 31 May 2011 21:06:00 GMT

Robert,

The WAN accelerator in our scenario was a Riverbed. I don't have any details on how it was implemented, etc. We treated it as a black box - our go live dates got in the way of working with the Network team and performing proper troubleshooting.

re: Transactional Replication and WAN links

Robert L Davis — Tue, 31 May 2011 21:53:19 GMT

See, I even got the name wrong. Yes, Riverbed. Not Bedrock. It may be Tuesday, but my brain thinks it is Monday.

re: Transactional Replication and WAN links

Dan — Wed, 01 Jun 2011 14:18:15 GMT

Argenis, how did robocopy work for you? We had to copy a 4TB VLDB and used all sorts of copy utilities and all worked terribly due to limitations on buffered copies. They would start fast and gradualy slow down to a trickle.

I ended up finding a few articles that recommend using Exchange's ESEUTIL and we then were able to get a sustained 650MB/sec throughput. Even if lightspeed cut the backup down to a few hundred GB, I'd still recommend using the ESEUTIL for a faster copy.

http://blogs.msdn.com/b/granth/archive/2010/05/10/how-to-copy-very-large-files-across-a-slow-or-unreliable-network.aspx

re: Transactional Replication and WAN links

Argenis — Wed, 01 Jun 2011 15:54:11 GMT

Dan,

robocopy worked pretty well for us. One thing we did to prevent copy problems was to perform the remote copy between two servers that weren't all that busy, and we made sure we always pulled the file - i.e, started the copy at the remote location.

re: Transactional Replication and WAN links

Sankar Reddy — Wed, 01 Jun 2011 16:13:56 GMT

To copy (large) files over the network, I am using winRAR to split the file into multiple smaller components and then transfer the smaller chunks. If something fails, I just have to re-start that one smaller file instead of re-trying the complete large file again.

re: Transactional Replication and WAN links

Dave — Fri, 03 Jun 2011 07:11:30 GMT

Very interesting thanks. We replicate to subscribers in the same datacentre as well as remote ones, and although we have a fat pipe between the datacentres I've definitely noticed that the remote subscribers take a lot longer to initialize than the local ones.

Is it still possible to initialize from backup when publishing only a subset of data? I wouldn't think so, but haven't had any experience with it.

re: Transactional Replication and WAN links

Argenis — Fri, 03 Jun 2011 15:46:42 GMT

Sankar,

In our case the backup files were split. That also helped :)

re: Transactional Replication and WAN links

Argenis — Fri, 03 Jun 2011 15:51:40 GMT

Dave,

Sure you can. You'll just end up with unfiltered data at the subscriber and it would be up to you to _carefully_ deal with that fact.

re: Transactional Replication and WAN links

Kendra Little — Wed, 15 Jun 2011 21:59:19 GMT

This is great! I'm adding this to my list of great links on replication.

re: Transactional Replication and WAN links

Will S — Thu, 18 Aug 2011 17:07:05 GMT

Hi Argenis. Were your subscriber servers also running Windows/SQL 2008 R2? Just wondering if it's required on both ends to see the TCP/IP improvements. Thanks!

re: Transactional Replication and WAN links

Tom — Sat, 11 Aug 2012 07:49:36 GMT

Argenis ,

Can you help me how setup "WAN" Replication (transaction) in SQL Server 2008 R2

I can't find it into the net

tanx