[Blink] Blink Ubuntu DNS lookup deadlock?

[g4-lisz at tonarchiv.ch]

Hi there

A few days ago I updated my OS to Pop! OS / Ubuntu 22.04 LTS with the 
Blink flatpack V5.5.0

A few times it worked flawlessly, but most of the time, starting a call 
lags a lot and it simply fails with a beep after a few minutes without 
any further message.

The logs shows issues with DNS:

2022-11-29 15:22:37.533993 [blink 2]: DNS lookup NAPTR 
guest1.voipgateway.org failed: no DNS response received, the query has 
timed out
2022-11-29 15:22:37.534465 [blink 2]: DNS lookup SRV 
_sip._udp.guest1.voipgateway.org failed: no DNS response received, the 
query has timed out
2022-11-29 15:22:37.534699 [blink 2]: DNS lookup SRV 
_sip._tcp.guest1.voipgateway.org failed: no DNS response received, the 
query has timed out
2022-11-29 15:22:37.534909 [blink 2]: DNS lookup SRV 
_sips._tcp.guest1.voipgateway.org failed: no DNS response received, the 
query has timed out
2022-11-29 15:22:37.535100 [blink 2]: DNS lookup A 
guest1.voipgateway.org failed: no DNS response received, the query has 
timed out
2022-11-29 15:22:37.637499 [blink 2]: DNS lookup TXT 
xcap.guest1.voipgateway.org failed: DNS record does not exist
2022-11-29 15:23:08.049049 [blink 2]: DNS lookup NAPTR 
guest1.voipgateway.org failed: no DNS response received, the query has 
timed out
2022-11-29 15:23:08.049976 [blink 2]: DNS lookup SRV 
_sips._tcp.guest1.voipgateway.org failed: no DNS response received, the 
query has timed out
2022-11-29 15:23:08.050817 [blink 2]: DNS lookup SRV 
_sip._tcp.guest1.voipgateway.org failed: no DNS response received, the 
query has timed out
2022-11-29 15:23:08.051510 [blink 2]: DNS lookup SRV 
_sip._udp.guest1.voipgateway.org failed: no DNS response received, the 
query has timed out
2022-11-29 15:23:08.052161 [blink 2]: DNS lookup A 
guest1.voipgateway.org failed: no DNS response received, the query has 
timed out
2022-11-29 15:23:38.498519 [blink 2]: DNS lookup NAPTR 
guest1.voipgateway.org failed: no DNS response received, the query has 
timed out
2022-11-29 15:23:38.498998 [blink 2]: DNS lookup SRV 
_sip._udp.guest1.voipgateway.org failed: no DNS response received, the 
query has timed out
2022-11-29 15:23:38.499612 [blink 2]: DNS lookup SRV 
_sip._tcp.guest1.voipgateway.org failed: no DNS response received, the 
query has timed out
2022-11-29 15:23:38.500547 [blink 2]: DNS lookup SRV 
_sips._tcp.guest1.voipgateway.org failed: no DNS response received, the 
query has timed out
2022-11-29 15:23:38.501826 [blink 2]: DNS lookup A 
guest1.voipgateway.org failed: no DNS response received, the query has 
timed out
2022-11-29 15:24:08.946267 [blink 2]: DNS lookup NAPTR 
guest1.voipgateway.org failed: no DNS response received, the query has 
timed out

and so on.

But in reality there are no DNS timeouts. IMHO the issue is that Blink 
doesn't handle the DNS answers right and then somehow deadlocks on the 
first NATPR request.

I did some sniffing on port 53 and there are no DNS requests for SRV:

192.168.178.23        192.168.178.1         DNS      82 Standard query 
0x1eab NAPTR guest1.voipgateway.org
192.168.178.1         192.168.178.23        DNS      162 Standard query 
response 0x1eab NAPTR guest1.voipgateway.org CNAME ws1.voipgateway.org 
SOA ns1.backbone.ch
192.168.178.23        192.168.178.1         DNS      79 Standard query 
0x3a0b NAPTR ws1.voipgateway.org
192.168.178.1         192.168.178.23        DNS      141 Standard query 
response 0x3a0b NAPTR ws1.voipgateway.org SOA ns1.backbone.ch
[ ..nothing concerning VOIP...]
192.168.178.23        192.168.178.1         DNS      82 Standard query 
0xb5c0 NAPTR guest1.voipgateway.org
192.168.178.1         192.168.178.23        DNS      162 Standard query 
response 0xb5c0 NAPTR guest1.voipgateway.org CNAME ws1.voipgateway.org 
SOA ns1.backbone.ch
192.168.178.23        192.168.178.1         DNS      79 Standard query 
0x5cba NAPTR ws1.voipgateway.org
192.168.178.1         192.168.178.23        DNS      141 Standard query 
response 0x5cba NAPTR ws1.voipgateway.org SOA ns1.backbone.ch
[ ..nothing concerning VOIP...]
192.168.178.23        192.168.178.1         DNS      82 Standard query 
0x63b5 NAPTR guest1.voipgateway.org
192.168.178.1         192.168.178.23        DNS      162 Standard query 
response 0x63b5 NAPTR guest1.voipgateway.org CNAME ws1.voipgateway.org 
SOA ns1.backbone.ch
192.168.178.23        192.168.178.1         DNS      79 Standard query 
0x6dce NAPTR ws1.voipgateway.org

The queries timeout occurs because Blink does not issue the requests. 
IMHO Blink does not handle the SOA replies and somehow deadlocks, so 
other requests are never sent.

Instead it should simply return: NAPTR record does not exist. Go on...

Cheers
Till