Performing a Rebuild of the Fabric

This chapter explains how to rebuild your fabric.

Rebuilding the Fabric


Caution

This procedure is extremely disruptive. It eliminates the existing fabric and recreates a new one.

This procedure allows you to rebuild (reinitialize) your fabric, which you may need to do for any of the following reasons:

  • To change the TEP IPs

  • To change the Infra VLAN

  • To change the fabric name

  • To perform TAC troubleshooting tasks

Deleting the APICs erases the configuration on them and brings them up in the startup script. Performing this on the APICs can be done in any order, but ensure that you perform the procedure on all of them (every leaf and spine in the fabric).

Before you begin

Ensure that the following is in place:

  • Regularly scheduled backups of the configuration

  • Console access to the leaves and spines

  • A configured and reachable CIMC, which is necessary for KVM console access

  • No Java issues

Procedure

Step 1

If you would like to retain your current configuration, you can perform a configuration export using the following procedure: http://www.cisco.com/c/en/us/td/docs/switches/datacenter/aci/apic/sw/kb/b_KB_Using_Import_Export_to_Recover_Config_States.html

Step 2

Erase the configuration on the APICs by connecting to the KVM console and entering the following commands:

  1. >acidiag touch clean

  2. >acidiag touch setup

  3. >acidiag reboot

Ensure that each node boots up in fabric discovery mode and is not part of the previously configured fabric.

Note

 

The acidiag touch command alone is not useful for this procedure, because it does not bring the APIC up in the startup script.

Caution

 

It is extremely important that you ensure that all previous fabric configurations have been removed. If any previous fabric configuration exists on even a single node, the fabric cannot be rebuilt.

Step 3

When all previous configurations have been removed, run the startup script for all APICs. At this point, you can change any of the above values, TEP, TEP Vlan, and/or Fabric Name. Ensure that these are consistent across all APICs. For more information, refer to: http://www.cisco.com/c/en/us/td/docs/switches/datacenter/aci/apic/sw/1-x/getting-started/b_APIC_Getting_Started_Guide/b_APIC_Getting_Started_Guide_chapter_01.html#concept_F46E2193E3134CD090B65B16038D11A9.

Step 4

To clean reboot the fabric nodes, log in to each fabric node and execute the following:

  1. >setup-clean-config.sh

  2. >reload

Step 5

Log in to apic1 and perform a configuration import using the following procedure: http://www.cisco.com/c/en/us/td/docs/switches/datacenter/aci/apic/sw/kb/b_KB_Using_Import_Export_to_Recover_Config_States.html.

Step 6

Wait for a few minutes as the fabric now uses the previous fabric registration policies to rebuild the fabric over the nodes. (Depending on the size of the fabric, this step may take awhile.)