Brocade DS-6505 SAN Switch Interconnecting Problem

If I need to merge two fabrics, I am always using a diff tool like Vim to compare the Brocade config Files:

• The Domain IDs needs to be unique;
• The switch priorities might be different;
• All other fabric settings must match each other.

If a Domain ID needs to be changed this will be disruptive for the attached devices. Depending on the attached servers, reconfiguring devices pathes, failover/multipath, security, aso. might be required, too. 

Depending on your supplier, it might be possible that some settings – like In Order Delivery or Routing Policies are different and needs to be corrected as required.

If all switches config files will match, I would create and enable a new zoneSet containing the zones from both active zoneSets and would merge the 3rd switch into the existing fabric.

I would use this change to clean up and optimize the fabric and the new zone set, too.

For example, If not already in use, I would consider to introduce Brocade peer zoning: https://www.brocade.com/content/html/en/administration-guide/fos-740-admin/GUID-081187A7-01DC-4F19-A8C9-5FD83F89E3B0.html

Best regards,

Swen

Dear Swen,

Sorry, my mistake about the Domain ID.

Actually, after checking, my 2 x connected switch are of different Domain ID 1 and 2, however, my 3rd to-be-connected switch is also of Domain ID 1, so does it mean that when changing the 3rd to-be-connected switch from Domain ID 1 to Domain ID 3, then it's discruptive for its attached devices but there is no impact for the attached devices in the 2 x connected switches?

How about when I add the 3rd connected switch configuration into the 2 x connected switch to form a common configuration, would it be discruptive for the attached devices in the 2 x connected switches???

Thanks for any advise.

Dear Swen,

Are you saying that by connecting a 3rd switch to the 2 x connected switch, it might result in the discruptive change of domain ID of the 2 x connected switch because of the Fabric Principle configured settting, and therefore, it's better to set the Domain 1 switch to the highest priority 3 ???

Is there anyway to tell the current fabric principle setting of each of the 3 switches???

If the 2x connected switches running domain ids will be 1 and 2, there is still the possibility that both switches will have - by default - a configured domain id of 1. In this case - while building the fabric - the fabric principal has kept domain id=1 but the subordinate had to switch its running domain id from configured = 1 to running = 2.

Having default domain ids and switch priorities, there is the possibility - depending on the switch WWNs and how the fabric will be merged - that the fabric principal will change. This would introduce the risk of switching the running domain IDs from 1 to 2 and from 2 to 1 disruptive.

If these default settings are in use, I would increase the fabric priority of the switch currently have running domain id = 1 to ensure, that this switch will become principal while merging the fabrics. This will be non-disruptive, the command for setting the switch priority to enforce a switch to become principal is "fabricprincipal --enable -p 0x01".

To change the 3rd switches domain id will be disruptive for the nodes attached to the 3rd switch.

To activate a new zoneSet - containing all zones from both fabrics - will be online. In the case that port zoning will be in use, remember that the domain ID from the 3rd switch will change.

First, I would check how the 2x domain IDs are configured.

If both are set to default = 1, changing the configured domain ID will require to disable the Brocade switch. If it would be possible to disable the switch, go ahead and change the domain ID as required.

Otherwise, instead of changing the configured domain ID, consider to check the switch priorities and ensure, that the switch having domain ID = 1 will have the highest priority. Then it will keep the principal switch role and its domain ID in case of the Build Fabric (BF) while merging the 3rd switch to the 2x switches.

You can use the command fabricprincipal --show to verify the current setting.

To identify the current principal switch, you can use the fabricshow command.

In the example bellow the ">" indicates, that "sw180" will be the current principal switch:

switch:admin> fabricshow

Switch ID     Worldwide Name               Enet IP Addr          FC IP Addr          Name

------------------------------------------------------------------------------------------------------------------

64:fffc40     10:00:00:60:69:00:06:56     192.168.64.59     192.168.65.59          "sw5"

65:fffc41    10:00:00:60:69:00:02:0b   192.168.64.180   192.168.65.180     > "sw180"

66:fffc42     10:00:00:60:69:00:05:91     192.168.64.60     192.168.65.60          "sw60"

67:fffc43     10:00:00:60:69:10:60:1f      192.168.64.187    0.0.0.0                      "sw187"

The Fabric has 4 switches

Fabric Name: mainFabricA

Please note, that I changed my suggestion from "fabricprincipal --enable -p 0x03" to the highest possible priority "fabricprincipal --enable -p 0x01"...

Sorry I made an incorrect statement.

The 2 x connected switches are of different domain ID, NOT the same domain.

What's the command to display the configured Domain ID???

My fabricprinciple --show display that the principle selection mode is disabled !!!!

to display the configured domain id, use "configShow | grep domain"...

"fabric.domain" shows the configured domain id - if it has been configured. If this value does not appear, default configured domain id =1 will be used...

Must all the 3 x FC Switches be connected to one another?

Can I have the following connections??

Switch 1  --------------  Switch 2  --------------------- Switch 3

At above, I will have Switch 3 communicated with Switch 1 via Switch 2.

Is it a valid connection or do I need to also connect Switch 3 to Switch 1 directly?????

To form a fabric, the 3 switches must not been connected to one another.

However, if there are communications from Switch 3 to Switch 1, it will make sense to connect them directly.

core edge would be ok - but if there is traffic between the edge switches, I personally would prefer a full mesh...