v9 is EOL and has been for a year - we have been shouting this from the rafters for a long time. As you might have discovered, there will be no fixes.
No idea on your storage issues but then we aren't going to be fixing that anyway - I guess you have added bigger drives but not expanded the partitions.
CentOS 7 is not technically covered on your Dell:
https://www.dell.com/support/home/es-es/drivers/supportedos/poweredge-2950But some have had success:
https://forums.centos.org/viewtopic.php?t=59249Going to have to start by telling us what you see in dmesg for your hardware.
What cards are fitted, are they recognised, what happens when you run network etup etc?
Have you tried a basic CentOS 7 ISO and checked it all runs with that? Might be a live one you can test?
Koozali SME v10 is based on CentOS 7 so if that works then SME should.