This KB describes the maximum-ecmp limit on QFX5k which is working with Junos.

On QFX5k series switch running with Junos, there are some options to configure maximum-ecmp routes.  And it's default value is 64.

user@Switch# set chassis maximum-ecmp ?
Possible completions:
  16                   Maximum 16 ECMP routes
  32                   Maximum 32 ECMP routes
  64                   Maximum 64 ECMP routes

However, even if changed the value, it won't take effect on PFE.

user@Switch# set chassis maximum-ecmp 16

{master:0}[edit]
user@Switch# show chassis
maximum-ecmp 16;

{master:0}[edit]
user@Switch# commit
configuration check succeeds
commit complete

This is an expected behavior on QFX5k series switch running with Junos. Even if it is committed as different value, it will always be 64 at PFE as QFX5k does not support to change the value dynamically.

2025-10-31 : This KB can apply to Junos only. Added the description.
2025-02-20 : Article Created