topic Re: LACP on Passive Palo Alto in General Topics

LACP on Passive Palo Alto

michaelmertens — Thu, 10 Aug 2023 13:59:05 GMT

I am planning a new site and want to make sure my detailed design will not be a problem. I will have two PA-440s in Active/Passive High Availability mode. These will connect to a stack of Cisco C9300s. I will have an LACP port-channel connecting one port of each Cisco switch (ports g1/0/1 and g2/0/1 in the stack to PAN Eth 1 on act and PAN Eth 2 on Passive....As we do not do Path or Link monitoring for HA, I am trying to avoid losing a Cisco switch in the stack and black-holing to a passive PAN, or the active PAN not having a functional switch to forward to. Therefore, I'm planning a LACP channel to span both Cisco switches in the stack but one of LACP members goes to Pt 1 of the active PAN and the other member goes to the passive PAN. (Please see diagram).

My question: The passive PAN does NOT send LACP packets- correct? The PAN's passive member in the cluster DOES provide ethernet carrier on the port, I want to make sure it does NOT send LACPDUs, and the Cisco switch sees it as an active member of the port-channel and forwards packets to a passive PAN...I just want to make sure...

Thanks!!

Mike

Re: LACP on Passive Palo Alto

seb_rupik — Thu, 10 Aug 2023 14:17:49 GMT

Hi there,

Why would you connect half of your port-channel to a device that is not going to pass traffic?

The typical way of connecting a active/passive HA pair to a stack of switches would be to take two ports from each firewall and connect them across the switch stack:

PA1: Eth1 -> gi1/0/1 - Po1

PA1: Eth2 -> gi2/0/1 - Po1

PA2: Eth1 -> gi1/0/2 - Po2

PA2: Eth2 -> gi2/0/2 - Po2

You would then configure pre-negotiation on the passive port-channel to ensure sub-second failover.

LACP and LLDP Pre-Negotiation for Active/Passive HA (paloaltonetworks.com)

cheers,

Seb.

Re: LACP on Passive Palo Alto

michaelmertens — Thu, 10 Aug 2023 16:15:39 GMT

Seb., Agreed, I guess I wasn't thinking clearly this morning. I'm going back to your design/point. Thanks!

Mike