Robert Misior
How to access file system directly on Cisco Unified Messaging servers
Cisco Unified messaging servers such as Cisco Unified Communication Manager (CUCM), Cisco Unity Connection (CUC) or Unified Contact Center Express (UCCX) are all running on top of a Linux operating system - CentOS. Access to the underlying operating system is limited though a Cisco-made strictly controlled CLI interface in which access to arbitrary files or the bash shell is disabled. However you may need to access information on the filesystem.
Here are quick steps on how to access the bash shell using the Cisco Unified Communications Recovery Disk.
Note: In our example 12.0.1.10000-10-recovery.iso was used
Step 1.
Mount the Recovery ISO as a CD/DVD to your server. Select “Connected” and “Connect at Power On”
Step 2.
Reboot the server
Note: Only with the assistance from Cisco TAC bash can be accessed on a running server.
From CLI run: utils system restart
Step 3.
When you see “Welcome to Cisco Unified Communications Recovery Disk” screen Press Alt+F2 (this is really the key to this process)

After pressing Alt+F2 you should be placed in the bash shell

You have done it - Congratulations!
Note: If you want to enable the network support, you can run the following command:
ifconfig eth0 <host IP> netmask <Subnet Mask> up
route add default gw <Default GW IP>