Today we had planned to merge two VLANs and to reassign the netmask and gateway settings to one of our ESX servers and to all the virtuals in it. Due to a misunderstanding our network engineer (located in UK) performed the changes ahead of us modifying the settings on the ESX server service console.
Once we saw our ESX server go down from vCenter, we had to rely on iLO and vi to get the job done.
In order to fix these settings, I did the following :
modify the gateway:
once done, restart the network service:
service network restart
et voila 🙂
Of course, without iLO or any kind of lights out management console and no one on the remote location to help, you're good for a nice trip!