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Fibre Channel (SAN)

Occasional Visitor
Posts: 1
Registered: ‎07-13-2012

ISL Portspeed change Best Practice

Hi All,


I have a question about changing the ISL portspeed to edge switches.


Our current setup is that we have 2 core switches per site. Connected to these core switches are HP blade enclosure with different types of san swichtes. In the past we have limited the portspeeds to 4G. Now that our environment is growing, the 4G uplinks do not suffice anymore and need to be changed to 8G. No hardware change is required for this. Only issueing a portcfgspeed <port> 8 is enough.


I know there is some similar effect to spanning tree (forgot the fibre channel term) on fibre channel as well. I was wondering of there is a minimum delay for the fabric to come to rest before proceding to the next port.  We need to change 64 ISL portspeed in total.



Broadcom Moderator
Posts: 108
Registered: ‎03-29-2010

Re: ISL Portspeed change Best Practice

If you have the ports between switches trunked, you will need to disable trunking first. "switchcfgtrunk 0" will disable trunking on the entire switch. You may do each port individually by using portcfgtrunkport command. All ports in a trunk group must be disabled for the speed change to take effect.


Once that's done, you may change the port speed individually, or in groups. The change will only take a very short time, and use the portshow and portcfgshow to see that the speed is configured. Once you have completed the speed changes, re-enable trunking with switchcfgtrunk 1, and the E ports which were trunked will go back to trunk state.


Any and all information provided by me is for entertainment value and should not be relied upon as a guaranteed solution or warranty of mechantability. All systems and all networks are different and unique. If you have a concern about data loss, or network disconnection, please open a TAC service request for service through Brocade, or through your OEM equipment provider. If this provided you with a solution to this issue, Please mark it with the button at the bottom "Accept as solution".

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