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Jon_Combe_46146's avatar
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Dec 07, 2010

UCS file differences

I am trying to setup an automated process to regularly download the configuration of an F5 BIG IP device which is then stored in a CVS repository so that we always have the latest configuration file available, but also previous versions and I have come accross a problem.



If I run



bigpip config save config



I end up with a file with the file called /var/local/ucs/config.ucs



I then download this via SCP. This works however I've come accross the problem that everytime I download this file it's different (e.g. you do an md5sum on the file and get a different result) even if the devices configuration has NOT changed in any way. I have found that these files are actually a ".tar.gz" file with a different extension.



What is happening is that all but one of the files are identical but the modification time of some of the files (which I have listed below) change and a tar file stores the modification time of the file within it and so the UCS file appears different each time because of these updated modification times.


















However there is also a file within the UCS file called SPEC-Files which also differs every time because it also includes the modification times on some of the lines, for example:-



N /config/.ucs_base_mac a4a62a1ba3e8dfc7c5d1fa16b1da580a 33188 0 0 34 1291654090 -



Are these differences important? Is there an easy way for me to tell if the config has actually changed as it seems that downloading the UCS file and running a diff on it is not possible?



Also I noticed that the UCS file contains some symlinks, but the links point to files that are not within the UCS file. For example /config/ntp.conf is a symlink to /var/run/config/ntp.conf but this file is NOT in the UCS file which seems odd?




1 Reply

  • Hi Jon,



    When you run a config save, the config running in memory is saved to the files and then wrapped up in a tar ball. If you aren't running GTM, WAM or ASM, you could probably use a Single Configuration File (SCF) to do a config diff more simply. As the name implies, the SCF contains the full LTM configuration in a single text file. The one notable exception is the SSL certs/keys.



    You can create an SCF file using 'b export `/bin/hostname`.scf'. The output is written to /var/local/scf/ by default.



    See SOL8453 for details:



    SOL8435: Overview of the single configuration file (SCF)