Where can I set DNS TTL of 3CX FQDN?

[SECOIT GmbH]

Hi All,

One of my customers wants to use 3CX PBX but at this point in time they don't have a fixed IP address.

I'm using a 3CX FQDN in the format "[customer].3cx.de".
The problem is that this A record for the 3CX FQDN has a TTL of 6 hours. For a dynamic IP address it should be rather 1 minute so 6 hours is by far too long for a dynamic IP address. 6 hours DNS TTL means a huge downtime for some functionality every time the IP address changes.
Is there some place where I (or someone from 3CX) can set this?

Thanks
Michael

 

[jed]

Hi Michael

The Enterprise version should have only 2 min TTL.

/Jesper

 

[SECOIT GmbH]

Hi Jesper,

Thank you for your reply. Does that means Std/Pro can't use a dynamic IP address?
6 hrs for dynamic IP is completely impractical dynamic IP addresses.

Sounds like I'll have to use a Dynamic DNS service and use an own FQDN which would be unfortunate since it is quite comfortable to use a 3CX FQDN (don't have to worry about certificates for example).

Is anybody reading this thread successfully using 3CX Std/Pro with a dynamic IP address?


Thanks,
Michael

 

[jed]

Hi Michael

I think the 6 Hour TTL is a political decision, to give some benefit to use the Enterprise version.

That said, we have a costumer running PRO and Dynamic IP and the "failover" happens within 20 Min. on this installation using 3CX FQDN.

/Jesper

 

[SECOIT GmbH]

Hi Jesper,

20 Minutes? That means your customer is either extremely lucky or their DNS server is ignoring the TTL and keeps querying the authorative DNS server even the TTL has not expired yet.
I can easily manipulate my customer's DNS server but for any remote workers or when people are travelling (using hotel internet for example) that's out of my influence.

Well, guess I will need to use a Dynamic DNS service then and issue a own certificate.