Ran into an interesting issue that required me to put my newly learned Linux skills to the test!
After using Linux Academy for a few months to learn Linux, I ran into my first Linux tshooting scenario. I imported into AWS a copy of vCenter 5.5 Appliance. Now normally you should boot it up and see all the NICs right? Well for whatever reason this wasn’t the case, I only saw 1 NIC whereas the other two were just missing from my ifconfig output.
Now if this was a switch or Windows box I’d do a #show interfaces or a ncpa.cpl and see what NICs I see. Not the case here, all I had was a black console screen with some colored letters and a blinking cursor — here we go!
If you thought Google was your friend before, he’s about to become your BEST friend when it comes to learning/tshooting Python or Linux. One thing I really like transitioning from a vendor only product to an open source is that the whole world is open to helping out/posting scripts/fixing bugs/etc at a much quicker pace than the big companies do. And by doing a Google search I was able to find tons of free info people trying to solve this issue. Let this be yet another addition to that collection.
Anyhow, so first up — I had 3 NICs assigned to my vCenter Appliance box, but only 1 showed up for some reason. I went into the /etc/sysconfig/networking/devices and I only saw 1 NIC file there (ifcfg-eth0). That of course was one issue right there, I had to tell it it had more than 1 NIC and to also give it some config.
cd /etc/sysconfig/networking/devices cp ifcfg-eth0 ifcfg-eth1 cp ifcfg-eth0 ifcfg-eth2
There, I just made copies from eth0 and created two more NICs. I also did a vi ifcfg-eth2 and gave it some static IP info. For example…
DEVICE=eth2 BOOTPROTO=static STARTMODE=auto TYPE=ethernet USERCONTROL=no IPADDR=192.168.1.1 NETMASK=255.255.255.0 BROADCAST=192.168.1.255
ESC > :wq! to save my file
Next I created a symbolic link to so when I do a network restart, it’ll know where to find these files in /network/. This way, any changes done in the networking/devices dir gets replicated for me without needing to manage multiple copies of my NIC config. For that the command is…
ln -s /etc/sysconfig/networking/devices/ifcfg-eth1 /etc/sysconfig/network/ifcfg-eth1 ln -s /etc/sysconfig/networking/devices/ifcfg-eth2 /etc/sysconfig/network/ifcfg-eth2
Great, now restart the box or restart the network services via #service network restart. Now if you do a #ifconfig you’ll see the NICs! Hope that helps someone out there!