topic Re: High Availability Latency / Bandwidth Requirements in General Topics

High Availability Latency / Bandwidth Requirements

ET — Mon, 24 Nov 2025 16:17:49 GMT

What are the Latency / Bandwidth Requirements for HA1 interfaces links between 2 HA members?

I saw a similar discussion here, but there is no actual answer in it

https://live.paloaltonetworks.com/t5/general-topics/high-availability-bandwidth-latency-requirements/m-p/71357

There is another related article: Next-Generation Firewall :HA Timers, but the timers here are mostly intervals rather than Latency.

https://docs.paloaltonetworks.com/ngfw/administration/high-availability/ha-timers

So I need to order a circuit (link) between 1 firewalls with Geo-cluster, and I need to know the requirements for it.

Thx

Re: High Availability Latency / Bandwidth Requirements

JayGolf — Tue, 25 Nov 2025 01:26:32 GMT

Hi @ET ,

There are no officially published latency or bandwidth requirements for HA1. The real requirement is simply that the circuit is stable, low-loss, and not congested.

For real numbers, you'll have to capture the HA1 traffic between the peers or review interface counters/stats on an intermediate switch.

Re: High Availability Latency / Bandwidth Requirements

Brandon_Wertz — Tue, 25 Nov 2025 16:29:04 GMT

@ET -- What is your datacenter design / strategy? What is your desired firewall architecture/design? You shouldn't need a dedicated circuit just for HA. Like @JayGolf mentioned there isn't any specific guidance. It's more about criteria & and thresholds and making sure your settings in HA are aligned with what the circuit is delivering.

These settings can/should be tuned to the circuit the communication traverses.

Re: High Availability Latency / Bandwidth Requirements

reaper — Tue, 25 Nov 2025 16:48:40 GMT

latency for HA1 is not as critical as HA2 or HA3 since you're not synchronizing live session data.

The most important data sent over HA1 is the user-ID table and DHCP leases which in most cases will not cause immense havoc even if there is high latency

If you're worried about your FIB, you could consider running Active/Active without routing sync

https://docs.paloaltonetworks.com/pan-os/11-0/pan-os-admin/high-availability/reference-ha-synchronization

Re: High Availability Latency / Bandwidth Requirements

ET — Tue, 25 Nov 2025 20:26:22 GMT

These setting are mostly (if not all) about intervals between sampling. It's not related to latency to my understanding

Re: High Availability Latency / Bandwidth Requirements

ET — Thu, 27 Nov 2025 10:15:48 GMT

Thx

I would expect this to appear in official documentation (stable, low-loss, and not congested.)