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skullnobrains

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what consequences should i expect if i manually create vms on an ESXi host that used to be administered through a currently broken vcenter appliance ?

what consequences should i expect if i manually create vms on an ESXi host ?

SHORT BACKGROUND

there is broken a vcenter appliance that i expect to be running again at some point.

i do not think drs was ever enabled on that cluster.

i need to get some work done which implies creating a few vms. and i can hardly afford to fix the vcenter appliance beforehand since i have no idea how much time that would require. additionally i have existing scripts to do the job quickly on a separate bunch of esxi hosts that have no vcenter at all and where never in a cluster and would be happy to use them both right now and after the vcenter is back

INTERROGATIONS

will these new machines be picked automagically by the vcenter ? or can the vcenter be safely instructed to rescan the esxi host/hosts ?

should i expect vmotion features to work properly again once the vcenter kicks back in assuming they did work in the first place ?

any thing else i should be aware of ?

and as an extra subquestion, do you know if there is a command to run on an esx host that will display the cluster the esxi is part of ? if that is even meaningful...


thanks for sparing time for sharing
Avatar of Pete Long
Pete Long
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The ESXs and Guest VMs will continue to run.

>>will these new machines be picked automagically by the vcenter ?
When you add a new host to vCenter it imports all the guest VMs on that host

>>should i expect vmotion features to work properly again once the vcenter kicks back in assuming they did work in the first place ?
No vMotion wont work (your cluster is not up) - when your new one is up you will need to re-enable HA on the cluster, but vMotion will work once you have rebuilt.

Just deploy a new vCenter appliance, it's not much work, (make sure you have your licences before you start) or you will have 60 days to get them afterwards :)

P
Avatar of skullnobrains
skullnobrains

ASKER

there are existing licences which i should be able to retrieve from the appliance.
i managed to gain root access. it is a virtual appliance that is hosted on one of the esxis. it broke because of lack of maintenance. disk full since february, ^^, not because of a licence issue. it is running vsphere 6.0

the current situation is there are 0 visible machines. actually NOTHING shows in the inventory on the webui. apparently it is not hooked to a domain. i checked one of the esxis. does not seem to be in a domain either. i'm still trying to figure out how this was initially setup. maybe i'll be able to get it to work again somehow, maybe setting up a different one is faster.

i'm progressing slowly since i don't really know the network topology, and i'm gradually gaining access on the various equipments. ... and accessing a vm's bios over vnc over ssh over socks over a vpn __i may have lost track of the order__ is quite the challenge, not even mentioning typing shell commands, sigh

do you mean i can setup a different appliance, manually connect it to the esxis, and expect it to pick the running vms properly ? and be able to vmotion them afterwards ? will the existing hosts be included in the cluster ? the ones i created manually ?

should that be the case i believe i can both get the job at hand done and work on fixing the vcenter issue at the same time
ASKER CERTIFIED SOLUTION
Avatar of Andrew Hancock (VMware vExpert PRO / EE Fellow/British Beekeeper)
Andrew Hancock (VMware vExpert PRO / EE Fellow/British Beekeeper)
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>>do you mean i can setup a different appliance, manually connect it to the esxis, and expect it to pick the running vms properly ? and be able to vmotion them afterwards ? will the existing hosts be included in the cluster ? the ones i created manually ?

It will pick up the VMS yes - you will need to create a new datacenter object and a new cluster object then add the hosts, As Andrew points out you can log into VMware and get your licence keys.

P
ok, seems like good news : at least i can go on with my own work !

regarding the vcenter, if i go through creating a new dc and a new cluster on a new appliance, i'm concerned about the existing cluster. can/should i pick the same names or possibly ids ? what about the semi working existing appliance ? i'd assume having the same esx in multiple clusters would end up in a mess and i'm pretty sure the licence does not cover vcenter ha if it is optional.

the current status is i have reasons to believe the existing appliance more or less works. i can see connections to the different esxs ports 443 so something is working. my bet is the webui only is broken. i do not have the possibility to check whether the windows client would work properly. and i'm struggling trying to find a way to list the inventory from the command line in order to  confirm if my hunch is correct, but either the command line is really poor or i'm really tired but i can't seem to find any way to do any admin task from the command line on the appliance...

thanks for your help so far. ideas still welcome.
you will need to create a new datacenter object and a new cluster object then add the hosts

 i assumed "hosts" referred to esxs rather than guests in the previous comment
regarding the vcenter, if i go through creating a new dc and a new cluster on a new appliance, i'm concerned about the existing cluster. can/should i pick the same names or possibly ids ? what about the semi working existing appliance ? i'd assume having the same esx in multiple clusters would end up in a mess and i'm pretty sure the licence does not cover vcenter ha if it is optional.

vCenter Server is just a management server, ALL these names are just friendly names for Humans, they do not really pay any real importance.

Turn off your existing broken appliance, and that's it, the hosts will not be communicating with it anymore...

You cannot have  hosts being managed by multiple vcenters, when you add your hosts to the new vCenter Server, it will advise they are being managed by vCenter A, just select yes, and they will be added to the new vCenter Server.

Then create the Datacentre, Cluster etc

Don't waste any more time, on the broken VCSA, it's not worth it, you'll be up and running with a new server (VCSA) in 30 minutes and all working again.
Hosts are ESXi Servers, VMs are Guests hosted on the ESXi servers.
when you add your hosts to the new vCenter Server, it will advise they are being managed by vCenter A, just select yes, and they will be added to the new vCenter Server.

that's the part i was uncertain about, thks.

i'll have to let the existing vcenter running for a while. there are actually users still using it through the c client. this infra is shared with an unknown number of other people...

anyways thanks for the confirmation
from what i gather in the thread, the answer is :

> the hosts can be created safely

> they will be picked up when the vcenter goes back online and work in the same way they would should they have been created through the vcenter.

> additionally some background : each esx is managed by one and only one vcenter. the vcenter manages all the esx's resources and creating hosts directly in the vcenter or on the esx does not make a difference. obviously don't expect migrations to work when using local storage.
correct, have a good day, glad to help you.