ServiceGuard and SONET

[Bob_Vance]

Has anyone had any experience with using ServiceGuard in a SONET transport environment?
(for the network + heartbeat and/or for mirroring the FibreChannel I/O in a stretched cluster configuration.)
Has anyone heard of any clusters working with SONET?
Does HP support it?
Does anyone know how to spell SONET?>)

tks
bv

[Deoncia Grayson_1]

Try this link..

http://h18002.www1.hp.com/products/quickspecs/11617_ca/11617_ca.HTML

[Bob_Vance]

Thanks.

I should be more specific.

I'm talking about a "stretched" Campus Cluster. I.e., the distance is more than 10km (it's actually about 10 miles) but we will still use LVM mirroring -- not array hardware replication.

The original proposed solution was using Brocade Extended Fabric solution (I think with Finisar transceivers) for the remote mirroring.
One issue there was that all 4 fiber pairs (2 for network, one for each site for (remote) mirroring) would be essentially in the same conduit.

But, now SONET is available. This would remove the worry one-conduit worry, as well as fiber maintenance.

tks
bv

[Richard Perez]

using SONET for the network/heartbeat shouldn't be an issue as the delay is low for a city-wide cluster. The issue with any transport method is disk mirroring because it is bandwidth and delay demanding. Usually you will need at least a DS-3 (45 Mbps) connection to do the mirroring.

But the question you should ask is: is it possible to transport Fibrechannel over SONET? I do know that you can use dark-fiber or DWDM to transport Fibrechannnel, but I am not aware of fibrechannel over SONET.

[Bob_Vance]

Thanks, Richard.

I agree with your assessment of the LAN/heartbeat situation. But, without someone's trying it, I guess we'll not know for sure.

As for the FC, Brocade's Web site says that they support FC over SONET, but I can't find any details thereof, yet. I'm thinking that the Brocade Extended Fabric solution, with the long-haul Finisar transceivers and Extended Fabric Software, with the extra buffer credits, would work the same whether the transport is dark fiber or SONET -- it seems to me that it should be transparent, as long as the latency is about the same.

tks
bv

[Duncan Edmonstone]

Bob,


Take a look at the following link:

http://h200006.www2.hp.com/bc/docs/support/SupportManual/c00244034/c00244034.pdf

Although this is a discussion of extending SANs for Continuous Access between 2 HP EVA disk arrays, the principles hold true for extending SANs for mirroring using MirrorDisk.

HTH

Duncan

[Richard Perez]

Bob
SONET is totally different from dark fiber. Dark fiber is just that: a point-to-point fibre without any element in-between. DWDM is used when you need go the extra distance with dark fiber.

SONET has active devices in the path (muxes) and the transmission is hierarchical. Brocade doesn't have gateways between SONET and FC that allows FC encapsulation, then you need to go with a third party product (Nortel or others)

Take a look at http://www.brocade.com/san/pdf/whitepapers/SANInterWP.pdf

[Bob_Vance]

Thanks, Richard.

My statement about transparency assumed that the requisite hardware was in place (either LH Gbic, DWDM, or SONET access). I meant that, as far as the Brocade switch goes, I would guess that it wouldn't know/care whether it was a simple LH Gbic using dark fiber or connected to a DWDM or SONET gateway.

In this case the SONET ring is private and already in place using some kind of Lucent hardware.

This stuff is currently over my head ;>) I haven't done any MAN/WAN FC (or SG) stuff.

tks
bv