topic Re: Standard practice for Virtual BMAC and SMLT SyS ID to be the same? in ExtremeSwitching (VSP/Fabric Engine)

Standard practice for Virtual BMAC and SMLT SyS ID to be the same?

Anonymous — Sun, 07 Feb 2021 18:20:24 GMT

Hi,

Recently seen a configuration being deployed that used the same value for both the SMLT Virtual BMAC and the LACP SMLT system ID, of say, 0200:00:41:ff.

I have for example used these values. believe these where taken from the configuration guide or training guide (maybe in part)

V_BMac = 00:00:84:04:01:01
SMLT Sys ID = 8201:63:22:11

Have seen somewhere a guide as to what to use, but can’t find it at this time.

Wondering if there are specific rules or formulas to follow here, and if it is typical to use the same values for for both BMAC and SMLT Sys ID, or using different values as above in the norm?

Many thanks

Re: Standard practice for Virtual BMAC and SMLT SyS ID to be the same?

Ludovico_Steven — Sun, 07 Feb 2021 23:14:08 GMT

Hi Martin

There are guidelines for the Smlt-Virt-BMAC; it has to be a unique BMAC in the fabric, so the convention is to re-use the BMAC of one of the vIST nodes and just changing the least significant byte.

Whereas there are no real guidelines for the LACP Smlt-sys-id other than it should be configured to the same value on both vIST nodes making use of LACP for one or more SMLTs links.

Both are configured as a MAC address, so instead of coming up with yet another id for the latter, one can simply re-use the same id as the former.

Best regards

Ludovico

Re: Standard practice for Virtual BMAC and SMLT SyS ID to be the same?

EXTR_Paul — Sun, 07 Feb 2021 23:22:18 GMT

What you are referring to I have seen in the old AVAYA ACE Fx-II training.

When configuring a viST cluster with custom System-IDs you are going to make the assumption the ID’s are going to be similar. EXAMPLE: switch 1 0000.0001.8401 and Switch 2 0000.0001.8402.

So its nice and clean to just change the last one or two characters to F or FF 0000.0001.84FF as the shared VIRTUAL-BMAC. And TBOMK that SMLT-VIRUTAL-BMAC value can be anything. The switch will throw an error if the value of the MAC address value is out of range or incorrect. And the Logs will return errors if its misconfigured on either switch of the vIST cluster.

But its also its important to remember that the SMLT-VIRTUAL-BMAC ONLY needs to be configured if you are using custom SPBm System IDs. If you are using the default BaseMAC as the system-ID you will just use BaseMAC’s as the SMLT-Peer-ID’s. The viST cluster by default will use the lowest BMAC from the two and there is nothing to configure.

Re: Standard practice for Virtual BMAC and SMLT SyS ID to be the same?

Anonymous — Mon, 08 Feb 2021 00:57:34 GMT

Thanks guys, very helpful, covered all the bases, so now well informed. Cheers.