12-01-2009 03:09 PM
I am looking to deploy virtual fabrics into my existing environment. My existing
environment is made up of 4900s, running 6.2.0g. I am adding/merging DCXs and
DCX-4Ss running 6.2.1b and logical switches into the existing fabrics.
In today's environment there is extended distance in use on some of the 4900s.
NONE of the 4900s have the "long distance fabric" option set. I am planning on
using extended distance on some of the logical switches being merged in, but I
wouldn't expect that the DCXs or DCX-4Ss would need the option either. I say this
because of the 6.2 Troubleshooting Guide, which states that the long distance
fabric option is "not necessary on Bloom-based, Condor, GoldenEye, Condor2, or
However, looking at the DCFM 10.1.4 User Guide, in the Virtual Fabric section,
it states that you should "select the Long Distance Fabric check box to enable
ISLs in a fabric to be up to 100 km long."
I should state that there is nothing in the 6.2 Administrator's Guide about having
to set the "long distance fabric" option.
So, do I really need this option or not? The Troubleshooting Guide makes it
sound like I don't need it. The Administrator's Guide is quiet on it. The DCFM
Guide is the one making the statement.
If I do need this option on the logical switches it is going to cause a lot of
pain since you can't ISL between switches that do and don't have the option.
Thanks in advance for any help.
12-01-2009 06:58 PM
--->>>....there is extended distance in use ....
--->>>So, do I really need this option or not?
how long ist the distance exactly ?
12-01-2009 07:26 PM
In order to use higher Port Speed, you need the Fabric license to set Higher value of Buffer Credit's, othewise the port work as L0 also Base, and you get a transfer rate of around 500KB, and I don't think make any sense to implement BIG's 8GB DCX's Director for 500KB transfer rate.
If you don't intended to use Extended fabric License in the DCX must use for this Port 4GB SFP and not 8 GB SFP, because the 8GB work only as 8,4,2 GBit/sec for FC Protocols, 4 GB SFP work as 4,2,1
12-02-2009 07:01 AM
First, thanks for the replies. However, I think you are confused in regards to what I
am talking about. I am not talking about the extended distance license, I have that.
What I am talking about is the "long distance fabric" attribute,
"fabric.ops.mode.longDistance". You can have the license without having the
attribute. You can also use LD, LS, etc without having the attribute set. Also, as
I pointed out in my question, the current Troubleshooting Guide states that you
don't need the attribute, "long distance fabric" for Bloom, Condor, Condor2,
GoldenEye, or GoldenEye2 ASICs. What is worrying me is that the DCFM Guide
appears to indicate that you need it for virtual fabrics.