[CentOS] Transition test report going from CentOS8 to Debian 10.

Thu Feb 4 15:39:22 UTC 2021
Lamar Owen <lowen at pari.edu>

Sorry for the length....


I'm posting this here since this particular transition has been 
mentioned on-list as one possibility for a path forward for current 
CentOS Linux users.  AlmaLinux, the Developer Subscription RHEL, Rocky, 
CentOS Stream, Springdale, upgrading to full RHEL; all these are also 
possibilities, too, and all have different strengths and weaknesses.  
The transition to Debian has a lot of strengths, including a long 
track-record of support (even if the support time for a particular 
release is shorter), a fully-open development model with no 'corporate 
overlord' that I know of, a large set of supported packages, and a huge 
community of developers and users.  For the CentOS user the main 
weakness is having to learn a few areas of difference in the way the 
system is setup and maintained; of course, if a ten-year 'stable' 
timeframe is really that important to you the lack of that is also a 
weakness.


So, last week I transitioned, as a test of sorts, my working CentOS 8 
main laptop to Debian 10.  I kept a complete backup of the C8 install 
should I wish to go back to it, and installed Buster to a new mSATA SSD, 
but ported the two SATA drives (Dell Precision M6700 - has an mSATA slot 
plus two SATA bays) straight over after making full backups.


I posted a pretty complete rundown on the scientific linux users mailing 
list, so I won't recap it all here.  The bottom line was the the 
transition was not any more difficult, really, than moving from CentOS 7 
to CentOS 8.  The software versions in Buster are pretty close to what 
is in CentOS 8, although I have yet to need any third-party repository 
(PPA) for anything I've needed to install.


All the packages I have worked with so far have worked fine with a 
little bit of massaging.  These include commercial (and costly) software 
such as Harrison Consoles' Mixbus32C, Qoppa's PDFStudio2019 
Professional, and others.

So if you were to decide that this is the route for you to take, it does 
work and I found it to be not nearly as hard as I had thought it might 
be.  If you install GNOME 3 you get GNOME 3; it feels pretty much the 
same as a non-Classic CentOS GNOME 3, just with a different set of 
extensions installed by default.

That's on the workstation.

On the server side, I'm evaluating Proxmox for the virtualization 
solution, and so far I'm finding it to be a pretty easy migration.  I'm 
using the 'non-subscription' repository, so this is a no-cost option.  
Even getting the box registered to our EMC Clariion SAN was relatively 
easy; EMC provides the Unisphere Server Utility for Linux x64 in RPM 
form; the latest I have is 
"ServerUtil-Linux-64-x86-en_US-1.0.55.1.0044-1.x86_64.rpm" (which is 
fairly old, but I did say Clariion arrays, so they're pretty old, too).  
Debian has provided the 'alien' tool for some time; after installing 
alien, a simple 'alien -i 
ServerUtil-Linux-64-x86-en_US-1.0.55.1.0044-1.x86_64.rpm' installed the 
EMC RPM in the correct place.  Proxmox already included everything that 
serverutilcli requires; on a plain Buster install I had to install 
dm-multipath and the device mapper libraries and tools before 
serverutilcli would find the arrays; but it ran just like it did on 
CentOS 8 (and 7).

I haven't decided whether to stay on Debian or not; too early to tell.  
I have time to test and evaluate.  My CentOS 7 installs aren't goin 
anywhere, though, at least until late 2023.  And I've registered for a 
Developer subscription of RHEL so that I can properly evaluate that 
option, too.

This is the beauty of open source: we have OPTIONS.