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liminal

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VMware VMs run fine, cant connect to host

Have a strange one. My VMs run fine, but cant connect to the hosts. have restated the management network and agents. Still wont connect.

What would be next?

Thanks
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kermanian
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probably the lock down mode is enabled.
you should go to the console of the VM Hosts and disable it. then you can use the vSphere to connect to the host directly.
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liminal

ASKER

My knowledge of VMware is pretty wide... but, have to say pretty shallow lol

it's my understanding that lock-down is to disable direct connections to hosts; ie vCenter only yes? SO I'm using vCenter, so guessing its not that :)
do you have ping to ip address of hosts. if you configure the different NIC for different vSwitch and one of them face a problem, then the vm can access to the network and host can not.
meantime, have you check for licensing issues, if your license expires you can not access.
as you havenot prepared enough info regarding the configuration of your VM I just have to guess what situation could cause your problem.
hope to be useful.
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ASKER

Oh I def appreciate the help :)

I can ping the host IPs... I'll check on licencing, but I never seen any alarms re that...

What other info do you need?
Are you able to connect to the host directly using the  vSphere client?


You restarted management agents, restarted vpxa,  restarted the host,  and still can't connect?

Something else to check would be working DNS,  ability of vCenter to resolve the hostnames of your ESXi servers, and ability of your ESXi servers to resolve vCenter's hostname.


Is vCenter on the same subnet and network segment as the ESXi hosts' management IP addresses, or is there a firewall/router / subnet boundary ?    Can the hosts ping vCenter ?   Is the host ESX or  is it ESXi?

ESX or ESX(i) Version 3.5, Version 4, Version 5?

Restarting management services... Did you use     /sbin/services.sh  restart    
specifically from an ESXi shell prompt that you used to restart management, or did you use a different method?

In some cases, you might need to stop the vCenter server agent on the ESXi Host as well, and issue a full re-connect.



There also needs to be bidirectional network connectivity between vCenter and ESXi on a  fairly large list of TCP and UDP ports, for all the vCenter management functions to work correctly and hosts to stay connected.
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ASKER

Are you able to connect to the host directly using the  vSphere client?

No, can ping it, but cant conect though vCenter or even just its webpage.


You restarted management agents, restarted vpxa,  restarted the host,  and still can't connect?

All except restarting the host... which I cant do in the middle of the day.

Something else to check would be working DNS,  ability of vCenter to resolve the hostnames of your ESXi servers, and ability of your ESXi servers to resolve vCenter's hostname. Connecting directly via IP doesn't work either.


Is vCenter on the same network segment as the ESXi host, or is there a firewall/router ?
Can the hosts ping vCenter ?   Is the host ESX or ESXi? Ok something interesting here. I cant ping anything. I get "socket returns -1 no buffer spaces available vmware" and it's ESXi 4.1

Is it     /sbin/services.sh  restart    
from an ESXi shell prompt that you used to restart management, or did you use a different method? it's ESXi so im doing it from the F2 page (for a lack of a better way to say it)

In some cases, you might need to stop the vCenter server agent on the ESXi Host as well, and issue a full re-connect. Yeah that was one of the first things I tried. As I said it cant even access the host webpage (so you can download the client ect)



There also needs to be bidirectional network connectivity between vCenter and ESXi on a  fairly large list of TCP and UDP ports, for all the vCenter management functions to work correctly and hosts to stay connected.

It was working few days ago... and nothing has changed in the topology

Thanks for the help with this
if I were you, I tried to connect to each host directly through vSphere client to be sure that the problem is related to the host or vCenter.
can you try to connect directly to hosts?
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ASKER

Yeah I have done that as well...

A bit more info, there are three hosts in this cluster. one is connecting to vCenter fine, but two are not.
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kermanian
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Yeah I was trying to do this without restarting the host... anyway thanks, ill just have to restart after hours
sorry mate, that was all i knew
"I cant ping anything. I get "socket returns -1 no buffer spaces available vmware" and it's ESXi 4.1"

The error suggests exhaustion of the memory reserve set aside for network buffering.
Check df.    Make sure you don't have a VMFS volume running out of disk space.

Check VMkernel IP configuration and host routing table.

esxcfg-route -l
esxcfg-vmknic -l

Are there any custom or special configuration adjustments that have been made in the Advanced configuration,  such as adjustments to resource limits, maximum mounts, etc..?
Did you just mount some additional shared storage targets?


Make sure there is a valid, enabled default gateway,  and the networks that should be there are there.

Check what kind of network card is installed on the server, and in particular... if the server vendor has any firmware updates for the NIC,  and you have any and all recommended  NIC driver updates made available in  ESXi patches  (or through the hardware vendor) installed.