Wednesday, August 31, 2011

Database Access

Many UC appliances (like CUCM, CUPS, etc.) use database to store configuration.  For security and supportability reason, the regular CLI provides limited access to database.  However, if you could get root access to the box, you would have full access.

su - informix

Change user role to 'informix' which is a built in Linux user to access the Informix database.

dbaccess $(dblutil -c) -

dbaccess is a SQL client to access Informix database.  'dblutil' is a DB role.

select * from licenseinfo

A standard SQL command to view all records in 'licenseinfo' table.

  • Press Ctrl-D to execute SQL commands
  • Press Ctrl-C to exit
  • On some terminals, you may have to press Delete to Backspace
If you want to know the relationship between different database tables, refer to "Data Dictionary" on CCO Docs.

To list all tables:
select tabname from systables where tabid > 99 and tabtype = "T"

Grab a some books like "SQL for Dummies" and test in your lab.

I wondered what does this do?  ;)

Tuesday, August 30, 2011

Root Access on Linux-based UC appliances

There are many posts on Internet teaching you how to get root access on CUCM.  This is not a secret.  Since CUCM is Linux-based, the method is pretty straight forward - use a Linux boot CD to boot into rescue mode and modify the relevant files.  Here's a simple walk through.

Assuming CUCM was already installed.  Boot the box with a Linux installation CD (e.g. RedHat).  Type "linux rescue" in the boot prompt.

Chose language.  Default is 'English':

Choose keyboard.  Default is 'US':

We don't need to set up network.  Thus choose 'No' here.

Choose "Continue" to mount the CUCM file system.

The following message is telling you that the CUCM file system has been mounted under /mnt/sysimage.  If you want to map the root directory to the CUCM file system (which is recommended), you may use command "chroot /mnt/sysimage".

Below are the commands and explanations.

chroot /mnt/sysimage

This is to map the root directory to CUCM file system.

cd /etc

Change the working directory to /etc, where most of the system configuration files are stored.

rm securetty

Remove file "securetty" to allow remote connections with root.

passwd root

Reset (change) password for the root user.  Type a password that is easy for you to remember.  Retype it to confirm.  If the password was changed successfully, you'll see the prompt "passwd: all authentication token updated successfully".

  • If you typed a simple password, you might get a warning like "BAD PASSWORD: it is based on a dictionary word".  Just ignore it and retype to confirm.
  • There's no screen display for the password you're typing.  Type carefully.

The following steps require some basic knowledge of the vi editor.  If you're not familiar with vi, please search Internet for vi commands help.

vi passwd

Change the passwd file so the root user has a shell (command line interpreter) to use.  Use vi commands.  Change the line

Save and exit file.

For those who are not familiar with vi, here are the command sequence (case-sensitive):
  1. Type /s to search for character 's'
  2. Type D to delete to the end of line
  3. Type A to enter append mode
  4. Type bin/bash to set the shell
  5. Press ESC key (it's a key on the upper-left corner of your keyboard) to exit append mode
  6. Type :wq to save and exit file.

vi ssh/sshd_config

Change the sshd_config file so you can SSH as root (it's disabled by default).  Use vi commands.  Change the line
Save and exit file.

For those who are not familiar with vi, here are the command sequence (case-sensitive):
  1. Type /Per to search for the word begins with 'Per'
  2. Type X to delete the letter on the left (which is '#' in this case)
  3. Type :wq! to save and exit this read-only file

Back to command prompt and type exit command twice to reboot the system.

Use a SSH client (such as putty) to test.  You should be able to SSH into CUCM with root account.

This method applies to all Linux-based appliances such as Unity Connection, CUPS, CER, UCCX (Linux version), etc.

P.S. If the active partition is /PartB, you might run into an error like this:
Just hit "Enter" key to get to the shell.  Then use the following commands:

mount --bind /dev /mnt/sysimage/dev
chroot /mnt/sysimage

Updated 3/13/2015:

I got many comments that "this works on CUCM version xx but didn't work on version yy".

Please understand that CUCM is just an application running on top of the RedHat Linux (which Cisco uses for many of its "appliances").

The rooting process is more OS related than application related.  If it didn't work, there could be only two reasons:

1) Some steps were missed or weren't done right (most likely).
2) RedHat changed how the authentication works between versions (very unlikely).

In a nutshell, the rooting is not specific to CUCM.  It's not even specific to Cisco.  You may root any appliance that is based on a common OS (such as Linux).

Last but not the least, this still works on my CUCM 10.5.  :)

Bypass CUCM/Unity hardware check

I was trying to install the UC 8.6.1 suite on my VMware ESXi.  I'm pretty savvy at VMware and UC, thus I didn't bother to download the OVA template from Cisco.  I created a VM with 75G hard drive and 2G RAM.

I had no problem getting UCM installed.  However, when it came to Unity Connection, I realized that the option was not presented on  screen like it did in previous versions (see below).

Maybe there's some magic in the OVA template.  So let's download it.

Open up the OVA file with Notepad.  You'll see that the minimum hardware requirement is 4G RAM and 160G hard disk.

If you're just testing it in the lab and want to save some hard disk space, you may choose "Thin Provision" while deploying the OVA.  VMware will dynamically allocate space as needed up to 160G.  ie. if the initial install occupies 75G, it'll only takes 75G physical space (even though the hard disk "looks like" 160G).  This is not recommended for production environment for performance consideration.

But if you're the kind of people that like to control everything, this is pretty annoying.  Why can't it just install on a 75G disk?  Ya, why not?  Let's hack it.

On the installation disc, look for the folder "Cisco/Install/conf".

Open the file "callmanager_product.conf" and search for "Unity Connection VMware rule".  A couple lines below, you'll see the line "NOT,   VMware,     *,      *,    *,      *,     *,      *,    *,      *".  Change it to "VAL,   VMware,     *,      *,    *,      *,     *,      *,    *,      *".  This will allow any virtual machine specification.

You may do the same if you want to use a physical server.  For example, if you have an old 7825H server and want to install Unity Connection 8.6.1 on it, just change the line "NOT,    7825H,     *,      *,    *,      *,     *,      *,    *,      *" to "VAL,    7825H,     *,      *,    *,      *,     *,      *,    *,      *".

You may also change the sections for CUCM and CUCM BE so they have less restricted requirements.

Save the file to the disc (image).  Boot from it.  Now you see the Unity Connection is available as shown below.

By the way, UC 8.6 supports VMTools (finally).  However the VMTools bundled with the install might not be up to date.


You may update the version from VM client.

The installation will take a while.  During install, you'll see the VMTools status as "not running".  This is normal.

When the install is completed, you'll see the version is updated.