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seq 10 permit ip any any

ACL Resequencing

ACL resequencing allows you to re-number the rules and remarks in an access or prefix list.

The placement of rules within the list is critical because packets are matched against rules in sequential order. To order new

rules using the current numbering scheme, use resequencing whenever there is no opportunity.

For example, the following table contains some rules that are numbered in increments of 1. You cannot place new rules between

these packets, so apply resequencing to create numbering space, as shown in the second table. In the same example, apply

resequencing if more than two rules must be placed between rules 7 and 10.

You can resequence IPv4 and IPv6 ACLs, prefixes, and MAC ACLs. No CAM writes happen as a result of resequencing, so there

is no packet loss; the behavior is similar Hot-lock ACLs.

NOTE: ACL resequencing does not affect the rules, remarks, or order in which they are applied. Resequencing merely

renumbers the rules so that you can place new rules within the list as needed.

Table 8. ACL Resequencing

Rules Resquencing

Rules Before Resequencing: seq 5 permit any host 1.1.1.1

seq 6 permit any host 1.1.1.2

seq 7 permit any host 1.1.1.3

seq 10 permit any host 1.1.1.4

Rules After Resequencing: seq 5 permit any host 1.1.1.1

seq 10 permit any host 1.1.1.2

seq 15 permit any host 1.1.1.3

seq 20 permit any host 1.1.1.4

Resequencing an ACL or Prefix List

Resequencing is available for IPv4 and IPv6 ACLs, prefix lists, and MAC ACLs.

To resequence an ACL or prefix list, use the following commands. You must specify the list name, starting number, and

increment when using these commands.

● IPv4, IPv6, or MAC ACL

EXEC mode

resequence access-list {ipv4 | ipv6 | mac} {access-list-name StartingSeqNum Step-to-

Increment}

● IPv4 or IPv6 prefix-list

EXEC mode

resequence prefix-list {ipv4 | ipv6} {prefix-list-name StartingSeqNum Step-to-Increment}

Remarks and rules that originally have the same sequence number have the same sequence number after you apply the

resequence command.

The example shows the resequencing of an IPv4 access-list beginning with the number 2 and incrementing by 2.

DellEMC(config-ext-nacl)# show config

ip access-list extended test

remark 4 XYZ

remark 5 this remark corresponds to permit any host 1.1.1.1

seq 5 permit ip any host 1.1.1.1

Access Control Lists (ACLs)

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