DNS Svr Records and Fusion Domains

[Andrew Pickett]

Hi

Ive follwed through the BDR and CYNC tuorials (With ease) to create a Fusion Cluster of 2 servers. Ive also installed the BDR app which i found in GITHUB which gives me an easy basic output for the replication.

To complete the failover im trying to workout how best to add the server records. With Fusion being domain based im confusing myself on how that effects the SVR record setup.

Any pointers would be great.

Kind Regards

Andy

 

[yaboc]

this is the config that works for me (added in dns zone editor of cpanel)

_sip._tcp.voip1.domain.com. 86400 10 100 5060 sip1.domain.com
_sip._udp.voip1.domain.com. 86400 20 100 5060 sip1.domain.com
_sip._tcp.voip1.domain.com. 86400 10 100 5060 sip2.domain.com
_sip._udp.voip1.domain.com. 86400 20 100 5060 sip2.domain.com

where voip1.domain.com is your fusionpbx domain and sip1 and sip2 are your clustered boxes.

you can used dig to verify the above entries are working and then switch your phone to use SRV instead of A entry.

got it from DigitalOcean Floating IP + Snapshot for quick restoring

 

[Andrew Pickett]

this is the config that works for me (added in dns zone editor of cpanel)

_sip._tcp.voip1.domain.com. 86400 10 10 5060 sip1.domain.com
_sip._udp.voip1.domain.com. 86400 10 10 5060 sip1.domain.com
_sip._tcp.voip1.domain.com. 86400 10 10 5060 sip2.domain.com
_sip._udp.voip1.domain.com. 86400 10 10 5060 sip2.domain.com

where voip1.domain.com is your fusionpbx domain and sip1 and sip2 are your clustered boxes.

you can used dig to verify the above entries are working and then switch your phone to use SRV instead of A entry.

got it from DigitalOcean Floating IP + Snapshot for quick restoring

That's great I'll have a go myself tomorrow!

 

[DigitalDaz]

Hmmm...

Just a quick scan of the above tells me that is not going to work well at all, the weights and priorities are all the same. This will effectively cause load balancing which absolutely will not work in FusionPBX, it will kind of work and in a lot of cases will seem to work but features will definitely be broken. You need an active/passive type solution where ALL calls are sent to the primary box and the backup only used in case of failure.

My live DNS records look like so, I only ever use TCP:

_sip._tcp.client1.mysuperpbx.com. 0 SRV 0 100 5060 pbx1-cluster1.mysuperpbx.com.
_sip._tcp.client1.mysuperpbx.com. 0 SRV 1 100 5060 pbx2-cluster1.mysuperpbx.com.

 

[yaboc]

DigitalDaz you're correct,
i did copy/paste from my cpanel and my edits got messed up. here's what should've been pasted initially. original post edited. thanks for catching this.

_sip._tcp.voip1.domain.com. 86400 10 100 5060 sip1.domain.com
_sip._udp.voip1.domain.com. 86400 20 100 5060 sip1.domain.com
_sip._tcp.voip1.domain.com. 86400 10 100 5060 sip2.domain.com
_sip._udp.voip1.domain.com. 86400 20 100 5060 sip2.domain.com

 

[phonesimon]

Hmmm...

Just a quick scan of the above tells me that is not going to work well at all, the weights and priorities are all the same. This will effectively cause load balancing which absolutely will not work in FusionPBX, it will kind of work and in a lot of cases will seem to work but features will definitely be broken. You need an active/passive type solution where ALL calls are sent to the primary box and the backup only used in case of failure.

DigitalDaz, can you say more about this? This is what I want to build, a load-balanced system with all the config and user data stored in a shared or replicated database. We should be able to make user-to-user, conference calls, VM, etc. all work as long as the data layer is shared and the cluster nodes all have ACLs for each other. I'd like to hear more about what will fail.

 

[DigitalDaz]

Loads will fail, no point in going through a list but as a simple example, call is on serverA you put it on hold, call is being held on serverA, you go to pick the call up, it gets sent to serverB but call is on serverA, call fails. Same with parking and much more, call center, you name it, it doesn't work with load balancing.

The only way we have it working at the moment is per domain load balancing, ie lock all calls from a single domain to a single server. That works.

 

[Kenny Riley]

Resurrecting this one..

I have a functioning cluster as well (Thanks Daz!) however, I am unable to get failover to work.

I have 2 A records created...

fpbx01-node-a.mydomain.com
fpbx01-node-b.mydomain.com

I have a test domain set up in FPBX - test.mydomain.com

I have two SRV records for this domain created as follows..
_sip._tcp.test. SRV 0 100 5060 fpbx01-node-a.mydomain.com.
_sip._tcp.test. SRV 10 100 5060 fpbx01-node-b.mydomain.com.

I can register an extension just fine by using test.mydomain.com as the hostname, I see the registration happen on Node A.

However, when I power down Node A and attempt to register to test the failover, I am unable to.

Any ideas?

Thank you!

 

[DigitalDaz]

What phones?

 

[Kenny Riley]

What phones?

I'm just doing a quick test using xlite. Confirmed the transport is set for TCP.

 

[DigitalDaz]

You may well find xlite doesn't even support srv

 

[Kenny Riley]

You may well find xlite doesn't even support srv

Good thought, let me try a hardphone and I'll report back.

 

[Kenny Riley]

No dice... Configured my Grandstream GXV3240 to use SRV and it registered just fine when node a was online.. powered node a offline, attempted to register again in hopes of registering with node b and nothing.

It looks like sngrep isn't included in this install so I may need to install it to see what's happening. Any ideas would be appreciated!

 

[DigitalDaz]

From what I can see the callcentric guys doing, are you putting the srv record in the outbound proxy field? They also just put in callcentric.com rather than the full srv record.

 

[smn]

Hmmm...

Just a quick scan of the above tells me that is not going to work well at all, the weights and priorities are all the same. This will effectively cause load balancing which absolutely will not work in FusionPBX, it will kind of work and in a lot of cases will seem to work but features will definitely be broken. You need an active/passive type solution where ALL calls are sent to the primary box and the backup only used in case of failure.

My live DNS records look like so, I only ever use TCP:

_sip._tcp.client1.mysuperpbx.com. 0 SRV 0 100 5060 pbx1-cluster1.mysuperpbx.com.
_sip._tcp.client1.mysuperpbx.com. 0 SRV 1 100 5060 pbx2-cluster1.mysuperpbx.com.

Why do you only use TCP?

 

[DigitalDaz]

Why do you only use TCP? It's harder on resources because of the stateful connection, although that is only a factor with a large number of connections on mediocre hardware.

Exactly, so the benefits you reap in NAT busting along with larger SDPs far outweigh it.