Wired Intelligent Edge

Hi,

I have two switches Aruba 8320 with VSX, ISL configurated with lag1.

There is a multi-chassis LAG configured:

interface lag 22 multi-chassis
    no shutdown
    no routing
    vlan access 1
    lacp mode active
    hash l4-src-dst
    lacp fallback
    lacp rate fast
    exit

interface 1/1/30
    no shutdown
    no routing
    lag 22

interface 1/1/29
    no shutdown
    no routing
    lag 22

The same is configured on switch 2, ISL and VSX seems to be fine and in sync.

When i boot using PXE with the mac-address, i do get the ip address that i have configured from the DHCP server but it does not download the files and proceeds to the other available interfaces which fails ofcourse.

When i remove the interfaces from LAG and they are just directly in the default vlan 1, it works fine. So its a proof that i can boot over PXE.

I believe it has something to do with `PXE ARP-11`

Looking forward.

Hi

I have a question to your setup. Is this an MC-LAG consting of 4 links (1/1/29 and 1/1/30 per VSX node)? How many interfaces are online when the system does PXE boot? 

What I have observed in a similar setup with a 8320 in a VSX cluster, that the LACP fallback does not always work on both nodes meaning that the switches may have some sort of mechanism in place to avoid loops by dropping traffic from all but 1 member of the LAG. My use case was not PXE but ZTP on access switches. The access switches do not know anything about the LAG / LACP with the factory default config, so I ended up in only configuring 1 interface into the core's LAG interface until the LACP config on the access switch was installed by the ZTP process and then add the second interface. 

Could you do a quick test and only configure 1 member in the MC-LAG interface and see whether that works similarly to a plain interface (without LAG configuration)? Please shutdown the other interface(s) and make sure that they are removed from the lag22. 

Could you also share the output of "show lacp inter" and "show int brief" and make sure the MAC address is seen on LAG22 when doing the PXE boot in your original setup?

Best, 
Thomas

interface lag 22 multi-chassis    no shutdown    no routing    vlan access 1    lacp mode active    hash l4-src-dst    lacp fallback    lacp rate fast    exitinterface 1/1/30    no shutdown    no routing    lag 22interface 1/1/29    no shutdown    no routing    lag 22