Grandstream UCM PBX settings

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charettepa
Just Passing Thru
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Grandstream UCM PBX settings

Post by charettepa »

I am having an issue finding the correct settings for
"Registration Expiry" and "Registration Retry Interval"

While i previously used Asterisk/FreePBX and prior to that ATA's and never had a problem
I have a Grandstream UCM PBX and the terminology is not lining up

I believe the i may have found "Registration Expiry"
but I am not sure
there is a "Max Registration/Subscription Time" and a "Default Registration Incoming/Outgoing Time"
which one should i set to 3600, if not both

for "Registration Retry Interval"
the closest i can find is "Register Timeout" which is right next to "Register Attempts" under outgoing SIP registrations
however the max i can set the value is 100

have i found the right field and if so, will this be a problem
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Liptonbrisk
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Re: Grandstream UCM PBX settings

Post by Liptonbrisk »

While I can't test, I would try this:

i) Registration Expiry 3600 seconds. The Expires value is what matters for FPL. Under 60 minutes won't work.

ii) Max Registration/Subscription Time 3600 seconds (The expiry value, I think, takes precedence).

iii) Register Timeout (next to Register Attempts) 100 seconds
While Freephoneline recommends 120s for the failed registration retry interval, 100 seconds should not produce a temporary IP ban. I would probably set Register Attempts to 3 or 4.

iv) See if you can find PBX Settings --> SIP Settings --> OPTIONS Keep Alive Interval. If you can find it (or something similar), set that to 20 seconds.
The setting might be under PBX Settings -->SIP Settings -->Basic Settings.

However, I don't have what you're using and am just guessing, unfortunately.

I'm also uncertain if I should be trying to help: "PBX connections or commercial uses are prohibited."
https://support.freephoneline.ca/hc/art ... redentials

Anyway, if you're just using FPL for residential usage (or as a hobbyist) and not for telemarketing, there shouldn't be a problem.
Please do not send me emails; I do not work for nor represent Freephoneline or Fongo. Post questions on the forums so that others may learn from responses or assist you. Thank you. If you have an issue with your account or have a billing issue, submit a ticket here: https://support.fongo.com/hc/requests/new. Visit http://status.fongo.com/ to check FPL/Fongo service status. Freephoneline setup guides can be found at http://forum.fongo.com/viewforum.php?f=15.
charettepa
Just Passing Thru
Posts: 17
Joined: 06/06/2010
SIP Device Name: PAP2T NA
Firmware Version: 5.1.6
ISP Name: Rogers Cable
Computer OS: Windows 7, XP, Ubuntu 10
Router: Asus Rt-N16 (DDWRT)

Re: Grandstream UCM PBX settings

Post by charettepa »

thanks so much for your reply
ill try when i get home

on the UCM
by default the MAX is 28,800 (8 hours) by default
but the default is 1800 by default
so i could change this to 3600

for the retry i will set it to 100 (the max they allow)
im a little concerned though as i dont want to get blocked
whats weirs is that google searches show the 120 is because
FPL allows max 10 attempts per 5 minutes
but that would be 60s retry not 120s
it would only be 120s if it was 5 attempts per 10 minutes
if I knew the actual max attempts I could set a higher max retries
it really would be best to leave the default of unlimited though

I will certainly look for keep alive as you suggested
the problem is the terminology that Grandstream is using


the Grandstream UCM's are all PBX'x that are built on Asterisk 16
its beyond me why they are using non-standard language
and imposing restrictions that are not there in Asterisk
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Liptonbrisk
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Re: Grandstream UCM PBX settings

Post by Liptonbrisk »

charettepa wrote: 03/12/2026
for the retry i will set it to 100 (the max they allow)
im a little concerned though as i dont want to get blocked
I've stated in other threads what the rate limit was in the past.

"As May 2013, our servers will rate limit REGISTER requests to a maximum of 10 requests per 5 minutes. Each authentication round usually consumes 2 requests (digest auth), so it is a fair number given our guidelines."
https://community.freepbx.org/t/trunk-s ... ca/22479/8
but that would be 60s retry not 120s
I believe Fongo (Fongo operates Freephoneline) was just being safe for the value they published. People reboot their SIP clients too, and each reboot makes a registration attempt.

Over a decade ago, one of my accounts was temporarily IP banned for making too many registration attempts within a short interval.
I had to stop trying to register for over an hour to clear the temporary ban.
The experience was annoying. I don't know what the rate limit is currently, and I don't want to test to find out.


I'm pretty sure you won't be temporarily IP banned for trying to make one registration attempt every 100 seconds up to 3 or 4 times. You probably wouldn't be temporarily IP banned if you set max attempts to unlimited with a 100 second interval, but I'm not positive either because I don't what the current rate limit is (it might be the same as it was in 2013 though, in which case you should be fine).
Please do not send me emails; I do not work for nor represent Freephoneline or Fongo. Post questions on the forums so that others may learn from responses or assist you. Thank you. If you have an issue with your account or have a billing issue, submit a ticket here: https://support.fongo.com/hc/requests/new. Visit http://status.fongo.com/ to check FPL/Fongo service status. Freephoneline setup guides can be found at http://forum.fongo.com/viewforum.php?f=15.
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Liptonbrisk
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Re: Grandstream UCM PBX settings

Post by Liptonbrisk »

Liptonbrisk wrote: 03/12/2026
iv) See if you can find PBX Settings --> SIP Settings --> OPTIONS Keep Alive Interval. If you can find it (or something similar), set that to 20 seconds.
The setting might be under PBX Settings -->SIP Settings -->Basic Settings.
I keep looking at different sources and finding different info, so I'm not sure about the setting locations. Probably need your specific device model

Maybe try this:

1. Set Keep-Alive for PBX

The path might be PBX Settings-->SIP Settings-->NAT.

i) Set NAT Traversal to Keep-Alive

ii) Click "Save"/Apply

2. Navigate to Extension/Trunk --> VoIP Trunks

i) Edit your Freephoneline trunk

ii) Navigate to the Advanced Settings, and find the Keep-alive Interval or OPTIONS Keep Alive Interval setting
(maybe the setting is called "Frequency" or "Keep-alive Frequency", depending on the firmware version and device model)

iii) For value, enter 20 (seconds).

iv) Keep-alive Message: ensure it is set to OPTIONS.

v) Save/Apply settings.


Again, I'm not sure, but maybe this info gives you a hint for where to look.
Please do not send me emails; I do not work for nor represent Freephoneline or Fongo. Post questions on the forums so that others may learn from responses or assist you. Thank you. If you have an issue with your account or have a billing issue, submit a ticket here: https://support.fongo.com/hc/requests/new. Visit http://status.fongo.com/ to check FPL/Fongo service status. Freephoneline setup guides can be found at http://forum.fongo.com/viewforum.php?f=15.
charettepa
Just Passing Thru
Posts: 17
Joined: 06/06/2010
SIP Device Name: PAP2T NA
Firmware Version: 5.1.6
ISP Name: Rogers Cable
Computer OS: Windows 7, XP, Ubuntu 10
Router: Asus Rt-N16 (DDWRT)

Re: Grandstream UCM PBX settings

Post by charettepa »

Liptonbrisk wrote: 03/12/2026
Liptonbrisk wrote: 03/12/2026
iv) See if you can find PBX Settings --> SIP Settings --> OPTIONS Keep Alive Interval. If you can find it (or something similar), set that to 20 seconds.
The setting might be under PBX Settings -->SIP Settings -->Basic Settings.
I keep looking at different sources and finding different info, so I'm not sure about the setting locations. Probably need your specific device model

Thank you so much for your quick replies and details
I have a UCM 6302 (latest series, mine has 2fxp and 2fxs)