[Koha] Advice for OS upgrade - Koha is installed

[SATISH]

Hi,

I have installed Koha 3.12.00 on Ubuntu Server 12.04 by packages method,
having 1000+ records.

Now, I am planning for Ubuntu OS upgrade from 12.04 to 14.04.
Even though, It is not a Koha related query, my intention is,  existing
Koha
should not get damaged, therefore, I would like to know, regarding
OS upgradation (Not Koha Upadation)

1) What are the precautions one should take, apart from taking MySQL DB
backup ?
2) Does OS upgrade affect the existing Koha,  Installed on System?
3) And any other related advice ..for OS Upgradation or best practices?

since, I never did an OS upgrade, your feedback is really help me to
proceed further!

With Thanks
Satish MV
Govt. Engineering College, Hassan
Karnataka, India.
+91-9449765737
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