Enable IPv6 Egress Filters

Use the boot config flags command to enable IPv6 egress filters and to add IPv6 egress qualifiers at startup.

About this task

This flag is disabled by default.

Before you begin

If more than 200 IPv4 egress entries exist in the configuration file, make a backup of the configuration file before you enable IPv6 egress filters. Only a maximum of 200 IPv4 egress entries are saved in the configuration file after you use the save config command.

For example, you can enter more than 200 IPv4 egress entries in the configuration file prior to enabling IPv6 egress filters. However, the entries are stored in ascending numerical order with ACL ID and ACE ID respectively, and not in the order in which they were added. Therefore, after you enable IPv6 egress filters and restart, and because the configuration file is read in ascending order, you receive an error message after the 200 maximum has been reached, such as:

CP1 [2017-09-28T00:44:24.077+05:30] 7K-Fi-94-I6:1 0x001049d4 00000000 GlobalRouter FILTER ERROR Unable to allocate data path resources for ACL ID 12.

Procedure

  1. Enter Global Configuration mode:

    enable

    configure terminal

  2. Enable the IPv6-egress-filter boot config flag:

    boot config flags ipv6-egress-filter

  3. Save the configuration, and then restart the switch for the change to take effect.
  4. After you restart the switch, verify that the IPv6-egress-filter boot config flag is configured to true:

    show boot config flags

Example

Switch:1>enable
Switch:1#configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
Switch:1(config)#boot config flags ipv6-egress-filter
Warning: Please save the configuration and reboot the switch
         for this configuration to take effect.
Note

Note

Flag support can vary across hardware models.

Switch:1#show boot config flags
flags advanced-feature-bandwidth-reservation low
flags block-snmp false
flags debug-config false
flags debugmode false
flags dvr-leaf-mode false
flags enhancedsecure-mode false
flags factorydefaults false
flags flow-control-mode true
flags ftpd true
flags hsecure false
flags ipv6-egress-filter true
flags ipv6-mode false
flags linerate-directed-broadcast false
flags logging true
flags nni-mstp false
flags reboot true
flags spanning-tree-mode mstp
flags spbm-config-mode true
flags sshd true
flags syslog-rfc5424-format true
flags telnetd true
flags tftpd true
flags trace-logging false
flags urpf-mode true
flags verify-config true
flags vrf-scaling true
flags vxlan-gw-full-interworking-mode false