I have crossed and interesting problem with networking on CUCM. I am currently running CUCM 10.5 and now upgrading to 220.127.116.1100 on Hyper-V (demo ofc). Version 11.0.1 is based on "Red Hat Enterprise Linux Server release 6.6 (Santiago)(3.10.0-514.e17.x86_64)".
When I set 1 virtual CPU on Hyper-V for version 10.5 or 11 network starts with "OK" (see bottom) and it doesnt go down until system shutdown is called - I can ping the machine.
Bringing up loopback interface: [ OK ]
Bringing up interface ethO: Deternining if ip address 192.168.G.100 is already in use for deuice ethO. [ OK ]
BUT, when I set more than 1 virtual CPU on Hyper-V for version 10.5 or 11, network starts also with "OK" (the same way as with 1 vCPU) and then it goes down right after couple of "Detecting Server Hardware" messages. Weird thing is that CUCM shows "no link" in both situations from "show network eth0" messages for both situations:
DHCP : disabled Status : up
IP Address : 192.168.0.100 IP Mask : 255.255.000.000
Link Detected : no Mode : Auto disabled, N/A, N/A
Duplicate IP : no
DNS: Not configured
Gateway : 192.168.1.1 on Ethernet 0
I am sure the network settings are the same, nothing changed, only the number of vCPUs are not equal 1. Why would RHEL or CUCM shutdown networking just because there are more then 1 CPU?
I can supply screenshots if needed.
Please no "this is unsupported" comments. Of course its unsupported and thats why i am asking professionals for help