vsphere 4 changing IP's

In the middle of a complete IP readdress for a customer.

All VM's have changed IP's fine and are running correctly but the vmware stuff just isn't happy.

I've added both the old & new IP to the vcenter box (& tried with just the new one) but as soon as I change it on the ESXi boxes (either from vcenter or the console) vcenter loses connectivity to them.

All the VM's still communicate fine but the host's don't ping from either a VM or from each other. It's like the ESXi boxes have isolated themselves (as I can't connect to them directly either).

If I try to add them as new hosts then vcenter says the host cannot be found.

If I change the IP's back on the hosts (& add the old vcenter box's IP as a 2nd address) then they reconnect fine.

Any ideas?

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jibbajabba

Have a look here

VMware KB: vCenter Server IP address change causes ESX hosts to disconnect

Plus, make sure the hosts resolve to the correct IP address. If your vCenter IP changes then you have to make sure you either change the DNS of the vcenter or add the new IP to the hostfile of the hosts and vice versa.

instant000

What jibbajabba said is probably the right answer.

You probably are adding these things by host names that won't resolve.

VMware KB: Configuring name resolution for VMware vCenter Server

saspro

instant000 wrote: »

What jibbajabba said is probably the right answer.

You probably are adding these things by host names that won't resolve.

VMware KB: Configuring name resolution for VMware vCenter Server

We're using the IP address not the hostname (does that matter?). But I'll try it anyway.

As soon as I change the IP's on the ESXi hosts they cannot ping each other, the gateway, the vcentre VM or any other host except themselves.

dave330i

Have you tried removing a host from vCenter, give the host a new IP, ping 1 of the VMs? Are the new IP address in the same subnet as the old IP? If they're in different subnet, it could be a network problem.

saspro

dave330i wrote: »

Have you tried removing a host from vCenter, give the host a new IP, ping 1 of the VMs? Are the new IP address in the same subnet as the old IP? If they're in different subnet, it could be a network problem.

Yup. But I'll try it again.

New IP's are a totally different subnet. VM's & ESXi boxes are on the same subnet.

The VM's are communicating with the network & users can use them fine no matter what the IP's on the physical hosts are.

instant000

saspro wrote: »

We're using the IP address not the hostname (does that matter?). But I'll try it anyway.

As soon as I change the IP's on the ESXi hosts they cannot ping each other, the gateway, the vcentre VM or any other host except themselves.

You may have a basic IP connectivity issue.

If you're using privates, could you post the IP and masks you're using, and make sure they're all in the same subnet?

dave330i

saspro wrote: »

Yup. But I'll try it again.

New IP's are a totally different subnet. VM's & ESXi boxes are on the same subnet.

The VM's are communicating with the network & users can use them fine no matter what the IP's on the physical hosts are.

I'm assuming that the 2 different subnet are on different VLANs? When you changed the host IP, did you remember to change the management network VLAN?

saspro

Vsphere 10.115.128.41 /24
Esxi1 10.115.128.35 /24
Esxi2 10.115.128.36 /24

VM's on 10.115.128.40-45 /24

gateway 10.115.128.2 /24

Everything looks OK on the switch etc

jibbajabba

saspro wrote: »

We're using the IP address not the hostname (does that matter?). But I'll try it anyway.

As soon as I change the IP's on the ESXi hosts they cannot ping each other, the gateway, the vcentre VM or any other host except themselves.

vSphere 5 will use IPs, vSphere 4 still uses hostnames and the IPs are also included in the self signed certificates so it wouldn't surprise me if you got SSL errors in your log when the hosts disappear.

Just ping the vcenter from the hosts and see to what it resolves, if it resolves to the wrong IP you know you have to use host files.

saspro

jibbajabba wrote: »

vSphere 5 will use IPs, vSphere 4 still uses hostnames and the IPs are also included in the self signed certificates so it wouldn't surprise me if you got SSL errors in your log when the hosts disappear.

Just ping the vcenter from the hosts and see to what it resolves, if it resolves to the wrong IP you know you have to use host files.

I'll give that a go.

Cheers

saspro

All solved.

I shutdown all VM's, changed the IP's in Vcenter then rebooted the hosts.

All connected up fine.

Thanks for everyones help