47 NOTICE Peer '1078-151303' is now UNREACHABLE!

Good afternoon

ive been looking into an issue that we are experiencing for a while now.
first the information about the infrastructure we are dealing with at the moment.
we got around 200 Yealink T42U and T42S devices connected, this over around 30 different offices around Belgium.

The Yealink devices
Register over 5060/udp to our asterisk server
The Server Expires timer is 600 seconds
and the retry rate is 5

The Keep alive type is Default (UDP) and the interval is 15 seconds

Firewall Fortigate 40F V7.0.12
we got a firewall policy allowing all traffic from internal to our WAN IP.
SIP ALG deactivated and the sip session kernel-helper-based and our local ISP is Telenet connected in bridging to the fortigate(s).

The Asterisk is hosted on a Linux

NAME=“CentOS Linux”

VERSION=“7 (Core)”

ID=“centos”

ID_LIKE=“rhel fedora”

VERSION_ID=“7”

PRETTY_NAME=“CentOS Linux 7 (Core)”

CENTOS_MANTISBT_PROJECT=“CentOS-7”

The Asterisk version is Asterisk 16.15.0

The SIP config we push

type=friend

host=dynamic

qualify=1500

insecure=port

nat=force_rport,comedia

;directmedia=nonat

disallow=all

allow=ulaw

allow=gsm

allow=alaw

callcounter=yes

busylevel=4

limit=6

accountcode=1231

setvar=SPYGROUP=1231

setvar=_TRANSFER_CONTEXT=1231-transfer

setvar=__TRANSFER_CONTEXT=1231-transfer

context=1231-guest

language=fl

directmedia=no

;rpid_update=no

rpid_update=yes

sendrpid=pai

directmedia=yes

disallowed_methods=UPDATE

The problem:
all devices go unreachable for exactly 10 seconds
the interval of this happening is mostly 1 minute 3 seconds but sometimes can last up to 20 minutes

Jan 25 09:26:47 NOTICE Peer ‘1078-151303’ is now UNREACHABLE! Last qualify: 16

Jan 25 09:26:57 NOTICE Peer ‘1078-151303’ is now Reachable. (17ms / 1500ms)
and I see the following in sngrep

If I missed information, please let me know

If someone knows a fix it would be greatly appriciated

Thanks in advance
Gauthier

In almost all cases this is network related in some way and outside of Asterisk, such that Asterisk configuration isn’t really at fault or can be changed to resolve it. Asterisk just sends the OPTIONS out and expects a response. If it gets no response, unreachable. Your packet capture shows no response, so something to do with networking or elsewhere.

hi Jcolp

Thank you for your time and reply.
The problem is that we don’t know where to look in the network to fix this, we tryed changing the keepalive function but that made it worse. the strange thing is that we have it on 20 different locations for the same server but also 10 locations without this issue.

thanks in advance

Can’t really help any further, aside from suggesting general troubleshooting and packet captures elsewhere.

Try changing your udp port from 5060 to something like 5070 this might do the trick for you