Change FQDN

[jofer]

Hi

I need some help here please. I have a V15 system and used the 3cx external FQDN. All my phones log in using the 3cx IP address. Now I need to move the 3cx server into a DR enviroment off-site which means the internal IP will change.
I have now asked the customer to create DNS entry and give me a SSL sertificate so that I can use the DNS name for registrations instead of the IP address.
So I want to make a full backup without the license and FQDN and reload it again using my internal FQDN supplied by the customer.

Then when I move the server into the DC and change the internal IP I only need to change the IP on the DNS entry to point to the new IP.

Do I have this right or am I missing something?

Regards,

 

[V..]

Hi Jofer,

All my phones log in using the 3cx IP address

reload it again using my internal FQDN supplied by the customer.

If your PBX is currently set to use the local IP address for local phones rather than internal DNS this will not work as you have hoped. If the phones are set to use the DNS internally than there will not be an issue with your plan but please ensure you take into account the DNS TTL.

If your phones do currently use the local IP rather than DNS I would reccomend the following:

1. Backup and restore the PBX changing the option to use DNS for both internal and external extensions.
2. Reprovision all of your extensions, they will now be using the internal DNS rather than the IP.
3. Proceed as planned.

 

[jofer]

Thank you V. That makes sense to me.

 

[jofer]

Just one more thing.

If I do it this way, do I need to release the existing FQDN, or will it just remain the same when I reload and use both external and internal FQDN?

 

[NickD_3CX]

If I do it this way, do I need to release the existing FQDN, or will it just remain the same when I reload and use both external and internal FQDN?

Yes, you will. Currently you have the External 3CX FQDN bound to your License Key. Assuming you plan on using the same key, you will have to release the 3CX FQDN from the key, so that when you install on the new DC, you will be able to enter the new External FQDN.
Internal FQDNs are not bound to the License Key, so if it were only for this you wouldn't have to.

One more thing about the certificate you plan to use. If you are going to be using Remote STUN or SBC IP Phones, make sure that the CA that will issue the cert is in the list of supported CAs of the phone manufacturer you are going to use, otherwise for STUN or SBC provisioning you will probably have trouble (for Local LAN its fine). For this best contact the Phone vendor directly or the Distributor where you get the phones from.