update DNS settings for VNET without restart of the VMs to take effect
Current when we try to update the DNS settings in the VNET or NIC, it required the VMs to be restarted to take effect. But when there are a large amount of VMs under the VNET, it would be a hard work to do so.
If this process could be simplify so that the restarted of VM will be no longer required, it would be a good news.
Thank you for the feedback. We’ll look into whether this can be included in our roadmap.
Dennis Cu commented
The following command worked for me without having ill-effect or requiring to reboot machine
To identify the current DNS settings and identify the name of the interface
netsh interface ipv4 show dnsservers
This command will set your IP settings to statically assign DNS.
netsh interface ipv4 add dns "Ethernet 3" 10.12.1.210 index=1 validate=no
netsh interface ipv4 add dns "Ethernet 3" 10.12.1.211 index=2 validate=no
netsh interface ipv4 add dns "Ethernet 3" 10.50.80.11 index=3 validate=no
netsh interface ipv4 add dns "Ethernet 3" 10.51.80.11 index=4 validate=no
This command will set your IP settings to ask for DNS settings from DHCP server.
netsh interface ip set dns name="Ethernet 3" source=dhcp
Note: If you haven't rebooted your machine, this will still set your machine to get the old DNS values. That's why you need to statically define it for now then set it back to automatically assign after the machine have been rebooted.
A nice option would be to use something similar to the scheduled notification and that it would force the VM's to do a release/renew after it reaches it's time limit. Or just use the agent in the VM to perform the action.
If somehow it fails, then the VM could reboot itself.
John Mason commented
Just do ipconfig /renew to refresh the dhcp settings after changing the DNS at vnet level.
Qing Liu commented
The VMs can also do a DHCP refresh from inside the VM and that will accept new DNS settings.
what's the status with this? It's been TWO YEARS! We don't have to do this with windows VMs in AWS, why do we have to do it in Azure?
Why is this still an issue? Come on Microsoft, this is really causing issues, and it has been known by you for over two years. Wake up and get it fixed. At least provide an update to your userbase....
Hebert Viana commented
Is Microsoft working on a way to prevent this restart?
Tommy Kuter commented
I can confirm this.
We need to update our secondary DNS configuration on about 200 VMs, and i just realized like you that a restart is needed.
It would be nice to see Microsoft working on this.
Hernán Fonseca commented
besides it's really annoying restarting +100 vms after changing the dns values on the vnet, also sometimes the new values are not been acquired after the vms are restarted so, you'll probably end up doing several restarts of your vms. how adorable is this?
Jag Sandhu commented
Is there any update for this? We will be changing our internal DNS servers, and dont fancy rebooting 100+ servers to get the new DNS address from the Vnet.
Alex Leong commented
It is not practical every time making just a small change to update the DNS setting in the VNET or NIC and it required the VMs to be restarted in order to take effect. It would be great if Microsoft can simplify the process.