[CentOS] Remote update OS from 6 to 7

[Giles Coochey]

On 29/08/2018 13:24, Jerry Geis wrote:
> Hello all...
> I have a remote machine running C6. I desire to update it to C7. Not
> possible to be on-site. Can I copy the Everything ISO for C7 to the
> machine,
> mount -o loop C7.Everything.iso  /media/cdrom
>
> then do a "yum upgrade" ?
>
> Will that work? The server is using software raid.
>
> Thanks
>
> Jerry
>
I've seen many comments discouraging trying to do this, let alone trying 
to do it remotely (and I assume you don't have IPMI, iLO or other 'bare 
metal' remote acess).

However, the process does not involve yum upgrade, you can check the 
following link which seems to go through the process in detail:

https://shaunfreeman.name/blog/upgrading-centos-6-5-to-centos-7-2

Be sure to complete the backup, and be ready to travel to site, or have 
remote-hands to restore the backup should the process go wrong.

Best Practice would be to configure a new Centos 7 system, and ship it 
pre-configured ready for a data transfer and migration of service to the 
new system, the decomission the old system and have it sent back to you.