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Elgreco
Contributor
Contributor

host FQDN

since Vmoton and HA relay on DNS im worried that my dns virtual servers would go down and the vcenter wouldn do HA

is it a good practice to write on each esx host and vcenter in the local host file FQDN of the servers/

in that case even if DNS the host would be able to see each other by fqdn

please an advice

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vmroyale
Immortal
Immortal

Hello.

Its always a good idea to have /etc/hosts set up properly on each ESX host. Check out kb 1012526 for an example of how to set it up correctly.

Good Luck!

Brian Atkinson | vExpert | VMTN Moderator | Author of "VCP5-DCV VMware Certified Professional-Data Center Virtualization on vSphere 5.5 Study Guide: VCP-550" | @vmroyale | http://vmroyale.com
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bulletprooffool
Champion
Champion

The DNS is really needed for setting it up in the first place - If you lost your DNS, the running heartbeats would continue to function and you will need invoke an HA event.

I would not use hosts files, if I could avoid it . . as these generaklly lead to problems in the future if you make any changes.

One day I will virtualise myself . . .
vmroyale
Immortal
Immortal

Wow, somehow I managed to completely miss that as of 3.5 U2 the hosts files were not needed!

With this being the case, stick with Alan's advice and leave out the added complexity of dealing with hosts files.

Brian Atkinson | vExpert | VMTN Moderator | Author of "VCP5-DCV VMware Certified Professional-Data Center Virtualization on vSphere 5.5 Study Guide: VCP-550" | @vmroyale | http://vmroyale.com
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Elgreco
Contributor
Contributor

I just read the thread 21640

Where they say:

---

For proper work HA you need:

1.

-nameserver in resolv.conf (nameserver must be accessible, contain all A and PTR records about all esx-servers in cluster)

or

-empty resolv.conf and records about all esx-servers in all /etc/hosts at all esx-servers in cluster.

2. ESX-server does not need any dns-records about vCenter.

3. HA works without vCenter.

TO proper work vCenter (DPM, DRS) you need:

  • accessible dns-server to resolve himself (vCenter) and to resolve all esx-servers in cluster (A and PTR)

or

-no specified dns-server field and all esx-servers in

windows/system32/drivers/etc/hosts (don't remember to add full name of

vCenter (like vcenter.domain.com), it need to resolve himself too)

P.S. If you use /etc/hosts-resolving and HA does not work, change all hosts records

192.168.100.115 esx1.domain.com

like this

192.168.100.115 esx1.domain.com esx1

---

It means that even puting the FQDN in the host file does not solve the problem

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Gerrit_Lehr
Commander
Commander

Using hostfiles should be absolutly fine if you can't use a propper DNS. In Windows, hostfiles have a higher priority then DNS anyway. Just make sure that the hostfile is correct and can resolv fqdm and hostname as mentioned in the other thread.

Kind Regards,

Gerrit Lehr

If you found this or other information useful, please consider awarding points for "Correct" or "Helpful".

Kind regards, Gerrit Lehr If you found this or other information useful, please consider awarding points for "Correct" or "Helpful".
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Elgreco
Contributor
Contributor

I ended up to use a third DNS running on physical server.

I will add it to the resolv.conf as a second failover host.

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