What is mean by principle switch

[ranjancom2000]

Can any one say me what is mean by principle switch on san fabric.

 

[heada]

The principal switch is the switch with the lowest domain number. This switch is the keeper of the master name database as well as the master of the zone/zoneset database.

-Aaron

 

[ranjancom2000]

Can you please advice me what is command to view the prinple switch.

 

[heada]

It depends on the vendor of the switch. For brocade switches, you can issue the command "switchshow" (this works for re-branded Brocade switches like the IBM 2109 switches)

It will give something like this:

rc3zsan01:admin> switchshow
switchName: rc3zsan01
switchType: 9.2
switchState: Online
switchMode: Native
switchRole: Principal
switchDomain: 1
switchId: fffc01
switchWwn: 10:00:00:60:69:51:4a:6d
switchBeacon: OFF
Zoning: OFF
port 0: id N2 Online F-Port 50:05:07:63:00:c4:9b:97
port 1: id N2 Online F-Port 10:00:00:00:c9:40:47:78
port 2: id N2 Online F-Port 10:00:00:00:c9:40:46:6a
port 3: id N2 Online F-Port 10:00:00:00:c9:4e:90:d1
port 4: id N2 Online F-Port 10:00:00:00:c9:54:66:3c
port 5: id N2 No_Light
port 6: id N2 No_Light
port 7: id N2 No_Light
port 8: id N2 Online E-Port 10:00:00:60:69:51:d6:45 "rc3zsan09" (downstream)
port 9: id N2 No_Light
port 10: id N2 Online F-Port 10:00:00:00:c9:30:f9:fa
port 11: id N2 No_Light
port 12: id N2 No_Light
port 13: id N2 No_Light
port 14: id N2 No_Light
port 15: id N2 Online E-Port 10:00:00:60:69:51:86:9e "rc3zsan05" (downstream)

There are other commands/methods for other vendors.

-Aaron

 

[Stephan]

Hi guys.

switchshow will show you the 'switchrole' of the logged on switch.
fabricshow will show you the switches within your fabric and show you the Principal switch. (the one with a >)

Technically, the Principal switch is the first one booted up within the fabric. I also thought (i must have read this somewhere), that the lowest WWN was the winner in the election of a Principal switch...not the Domain ID??

Here is how to deal with it, taken from the Brocade book...(don't know if it is your hardware though...is it the same command for Mcdata? Cisco?)

Synopsis fabricprincipal [-fhq][ mode ]

Description Use this command to set principal switch selection mode for the switch. The implementation of the fabricPrincipal command is based solely on mechanisms specified in the Fibre Channel standards. These mechanisms provide a preference for a switch requesting to be the principal switch in a fabric, but they do not provide an absolute guarantee that a switch requesting to be the principal switch will actually achieve this status. When dealing with larger fabrics, the selection of the principal switch is less deterministic. In these cases, to help ensure that the desired switch is selected as the principal switch, a small selection of switches should be connected together first, followed by the addition of the rest of the fabric.

Operands This command has the following operands:

-f Specify the -f option to force a fabric rebuild. This option is required when enabling principal switch mode. This option is not valid with the disabling principal switch mode.

-h Specify the -h option to display command usage summary.

-q Specify the -q option to display the current mode state.

mode Specify 1 to enable, or 0 to disable principal switch mode (the mode activates when the fabric rebuilds). This operand is optional.

To display the current mode settings: fabricprincipal -q
To disable the mode setting: fabricprincipal 0
To enable the mode setting: fabricprincipal 1
To enable and force a fabric rebuild: fabricprincipal -f 1

Steph

(hehehe. Looks like heada got to it 1st...! )

 

[ranjancom2000]

Thanks to everyone the information you have provided is very worth full to me.
Can you also able to provide me what is purpose of having naming service on fabric.

 

[buki]

For Cisco it is:
# sh fcdomain

VSAN 1
The local switch is the Principal Switch.
[..]

 

[vedmed]

Setting Switch Priority

By default, the configured priority is 128. The valid range to set the priority is between 1 and 254. Priority 1 has the highest priority. Value 255 is accepted from other switches, but cannot be locally configured.

Any new switch cannot become the principal switch when it joins a stable fabric. During the principal switch selection phase, the switch with the highest priority becomes the principal switch. If two switches have the same configured priority, the switch with the lower WWN becomes the principal switch.