Description

Filter action reject is not supported if it is applied as an output filter

Symptoms

A filter that is configured with action as reject cannot be applied as an output filter to an interface. When a commit is performed, it fails throwing the error "Referenced filter can not be used as reject not supported on egress"

 

Here the firewall filter is configured with action reject.

 

root@qfx5100# show firewall family inet filter monitor 

term last {

  then {

    reject;

  }

}

root@qfx5100# show interfaces xe-0/0/10 

unit 0 {

  family inet {

    address 10.1.1.1/24;

  }

}

 

When the filter is applied to the interface xe-0/0/10 on the outbound or as output filter then commit fails with error.

 

{master:0}[edit]

root@qfx5100# set interfaces xe-0/0/10 unit 0 family inet filter output monitor 

 

{master:0}[edit]

root@qfx5100# commit 

[edit interfaces xe-0/0/10 unit 0 family inet]

 'filter'

  Referenced filter 'monitor' can not be used as reject not supported on egress

error: Failed to read config

commit-check failed

 commit-check failed

error: configuration check-out failed

 

{master:0}[edit]

root@qfx5100# 

 

Solution

Configure a filter with action as discard than using reject if the filter will be used as output filter.

 

From the above example, modify the filter with action set to discard

 

root@qfx5100# show firewall family inet filter monitor 

term last {

  then {

    reject;

  }

}

{master:0}[edit]

root@qfx5100# 

 

root@qfx5100# delete firewall family inet filter monitor term last then reject 

 

{master:0}[edit]

root@qfx5100# set firewall family inet filter monitor term last then discard 

 

{master:0}[edit]

root@qfx5100# show | compare 

[edit firewall family inet filter monitor term last then]

-    reject;

+    discard;

 

{master:0}[edit]

root@qfx5100# commit 

configuration check succeeds

commit complete

 

 

Apply the filter to the interface xe-0/0/10

 

{master:0}[edit]

root@qfx5100# show interfaces xe-0/0/10 

unit 0 {

  family inet {

    address 10.1.1.1/24;

  }

}

 

{master:0}[edit]

 

root@qfx5100# set interfaces xe-0/0/10.0 family inet filter output monitor 

 

{master:0}[edit]

root@qfx5100# commit 

configuration check succeeds

commit complete

root@qfx5100# show firewall family inet filter monitor 

term last {

  then {

    discard;

  }

}

Modification History

04-18-2023 Initial KB.