Server -Storage -SAN

[avamar11]

Hi All,
Now this may sound a juvenile question to most of you ,but I am still asking it .Suppose I have 2 data centres spread (Primary and DR ) connected using dark fibre .I have 2 storage arrays (STORAGE A and STORAGE B one in each data centre .Server A is connected to PRI Storage ,now I want to know whether SERVER A can be connected to STORAGE B ,as I have fabric SWITCH at both sides .Usually SERVER at one side only sees STORAGE at that site ,while data from one STORAGE is replicated to another STORAGE array .Beside latency what else can prevent a server from seeing disk on remote storage ?

Thanks in advance....

[gabbar]

"now I want to know whether SERVER A can be connected to STORAGE B"

yes, it can be connnected.

"Beside latency what else can prevent a server from seeing disk on remote storage ?"

nothing will stop the Server A to see the Storage B apart from standard problem that any storage can face.


P.S: I had managed a similar setup where bunch of servers were presented storage from both EVAs which were in CA setup

[Víctor Cespón]

If you establish an ISL between a switch in site A and a switch in site B, you'll have a fabric that spans both sites and a server in site A can access storage in site B.

Obviously with a little more delay. How much delay depends on the distance, 5 microseconds per km.

[Tom Nieman]

I thought "dark fiber" really means there is nothing connected on either end... It's just a cable run for furture use... When it's used it's no longer dark. But I could be wrong...

So you really need to know the type of fiber run between the switches to have a better idea of what you can do... IE Short-Wave, Long-Wave, IP, etc.

Also, just to say it's a "fabric SWITCH" may be enough information, but it's probably best to identify the type of switch. IE CNT, Brocade, CISCO, etc...

Now are they considered to be in the same domain? are they on the same fabric? or is some other routing being done for the replication...

It all kind of matters before it can be determined whether the server can be connected to the replicated storage...

Also, you probably do not want to connect a server to the same luns on replicated storage side or you may get a split brain (serious outage) type event...

There are a lot of variables to answer your question with the greatest confidence.