Cisco IOS - Access-list resequence | GOLINE
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Cisco IOS – Access-list resequence

Paolo Caparrelli Cisco 22 June 2022

However, IOS includes a convenient command to resequence all entries in an ACL without a reboot and without recreating the ACL:

Router(config)# ip access-list resequence Foo ?

  <1-2147483647>  Starting Sequence Number



Router(config)# ip access-list resequence Foo 10 ?

  <1-2147483647>  Step to increment the sequence number



Router(config)# ip access-list resequence Foo 10 10

Router(config)# do show ip access-lists

Extended IP access list Foo

    10 permit ip host 10.0.23.23 any

    20 permit ip host 10.0.23.76 any

    30 permit ip host 10.0.22.144 any

    40 permit tcp any any eq www

    50 permit tcp any any eq 8080

    60 permit tcp any any eq 443

    70 permit tcp any any eq 4343

    80 permit udp any any eq domain

    90 permit tcp 10.0.8.0 0.0.3.255 any eq smtp

    100 permit tcp 10.0.12.0 0.0.1.255 any eq smtp

    110 deny ip any any log


The example above uses the default starting number and interval, however arbitrary values can be provided for both if you'd like a little more room to maneuver between entries:

Router(config)# ip access-list resequence Foo 100 50

Router(config)# do show ip access-lists

Extended IP access list Foo

    100 permit ip host 10.0.23.23 any

    150 permit ip host 10.0.23.76 any

    200 permit ip host 10.0.22.144 any

    250 permit tcp any any eq www

    300 permit tcp any any eq 8080

    350 permit tcp any any eq 443

    400 permit tcp any any eq 4343

    450 permit udp any any eq domain

    500 permit tcp 10.0.8.0 0.0.3.255 any eq smtp

    550 permit tcp 10.0.12.0 0.0.1.255 any eq smtp

    600 deny ip any any log


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