Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

Question from SAN Newbie

Traditionally we've always used NAS based storage for our server load balancing solutions.

With SAN, is it possible to set up shared storage that can be accessed by multiple servers simultaneously for the purposes of load balancing ? (web/email) I know you can configure individual storage volumes for use by individual servers but this is of lesser importance to us.

Also, which Cisco solution would be required for iSCSI mirroring of SAN data from one site to another ? The throughput of the write-thru is only on the magnitude of about 50Mbps.

Thanks,

= K

5 REPLIES
New Member

Re: Question from SAN Newbie

In a SAN multi Targets(storage LUN's) can be shared and accessed by multi Initiators(hosts) Clustering software on the host or SCSI reserve methods are used to lock that area on the disk so only one write operation can be working at a time. For reads all can be readin at same time. There are many ways to balance the I/O's to the targets on the SAN. As for mirroring with iSCSI where there is a local SAN connected Target and a iSCSI connected Target the I/O is sent to both, local copy and remote copy for reason of backup, what the application is to do this could be as simple as NTbackup. If your really wanting to push a backup or replication of the data from SAN to SAN then you would use FCIP protocol along with a application data mover on the array or a package like Veritas.

New Member

Re: Question from SAN Newbie

OK, I think I have a better handle on it now.

So, if my application is server load balancing, I should have no problem reading from the target LUN simultaneously from multiple readers ? (I'm not looking for the SAN equipment to perform the SLB, I already have switches for that)

I'm still a little confused about the iSCSI replication. I'd like to avoid needing to run backup software on the clients. I'd like to actually have the SAN equipment do the mirroring between the local fibre-channel SAN unit and the remote unit via iSCSI.

The goal is to have the SAN unit at the remote site contain a near-real-time duplicate of the local unit.

Is this possible ?

Thanks,

= K

New Member

Re: Question from SAN Newbie

Sync or async mirroring between 2 Storage systems on two different san's would most likly be done with FCIP. ISCSI is not a Target to Target protocol, it is Host to Target protocol. If the arrays you are using in your SAN's are the same vendor i.e. EMC or IBM, or HP, then there would be a application on the array controllers that will move the data over FCIP to the remote SAN with like Storage. If the Array on the remote SAN is not the same vendor type as the local then a third party data mover like Veritas is required, again no backup client is involved

New Member

Re: Question from SAN Newbie

Thanks again.

Just for clarification, the FCIP interface on the SAN gear is traditional ethernet ?

= K

New Member

Re: Question from SAN Newbie

It is 1-2 GiG Fible channel on the SAN side and GiGE on the Data network side.

188
Views
0
Helpful
5
Replies
CreatePlease login to create content