LACP rate slow vs fast... impact on bandwidth?

Question

Is there any impact on bandwidth when choosing fast (1s) LACPDU timing rather than slow (30s)?
Anyone ever bothered to measure?

I've always assumed it's negligable, with the simple act of bonding probably adding more overhead than any LACPDUs

score 13 · Accepted Answer · answered May 07 '15 at 00:32

13

An LACP PDU is around 110 bytes, so running them every second isn't likely to even register on an Ethernet link of any speed.

I would recommend running in "fast" mode at all times for rapid detection of faults.

answered May 07 '15 at 00:32

Benjamin Dale

Fantastic thanks. Slow mode at 30s does seem largely pointless these days. – batfastad May 07 '15 at 10:01

score 3 · Answer 2 · answered Oct 22 '16 at 00:35

3

For ISSU on Cisco NX-OS to work you need run LACP configured as "SLOW" and you still detect any issues with the port-channel!

answered Oct 22 '16 at 00:35

Jeffry

2 Answers2