Take the 2-minute tour ×
Server Fault is a question and answer site for professional system and network administrators. It's 100% free, no registration required.

I'm new to VMware and setting up an Esxi server as a trial with the intention of possibly virtualizing some of our servers in the near future. I have setup ESXi on a Dell poweredge server, and installed a Centos 5.6 and Ubuntu 11.04 guest os on the server. However I cannot get networking on my guest OS's. The host is connected to a network with a DHCP server via a switch and is configured with a static IP.

I have the default set-up for networking on the host: both guests are connected to the default vmnic1 adapter via the virtual switch vSwitch0. One thing though, the virtual adapter shows 'Observed IP ranges' to be XXX.XXX.XXX.194-XXX.XXX.XXX.195 (I've blanked out the initial prefixes) i.e just 1 address, even though the network the host is connected to has the usual subnet mask. On the guest machines (using DHCP) by default, I can see an eth0 interface but with no connection or assigned IP address. A physical machine connected to the network gets a DHCP lease as expected. How do I get networking working on my guest OSes? Apologies for the long-winded question.

share|improve this question
Do the guests show that link is up? Is the virtual switch configured with physical NICs that are connected to the network? If you give a guest a static IP on the network does it work then? –  mrdenny Aug 26 '11 at 17:57
The virtual switch is configured with the physical NIC (It seems the physical NIC is called vmnic1 or vmnic0 by default). No using static IP's doesn't work either. Yes the eth0 interfaces are up (or I can bring them up using ifup) but have no network connection. I'm assuming I don't have to manually add some virtual interface or anything else. –  JavaDev Aug 26 '11 at 18:16
vmnic0 should be the management port and vmnic1 should be the one for the VMs. They can be on the same switch, but that isn't recommended. When you edit the VMs properties does the vNIC show as connected to the correct vSwitch and that it's online? –  mrdenny Aug 26 '11 at 18:20
Ok I'm able to get static IP's working though not DHCP but now I guess thats probably a network problem and not an esxi problem. I just wanted to be sure that nothing else needed to be done esxi configuration-wise to get networking out of the box for my guests. –  JavaDev Aug 26 '11 at 20:20
If you've got a machine with a static IP working correctly and the guest is now able to talk to machines outside of the ESXi host then the network is working as far as ESXi knows. If DHCP is a problem at that point you'll want to check the physical network. ESXi won't be blocking anything at that point. –  mrdenny Aug 26 '11 at 21:49

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.