Here is a record of udp port 53 when my ppp0 connection is created
with the faulty SIM (tcpdump -s 0 -U -n -i any udp port 53):
I have compared it with a working SIM and it seems similar. Only
timestamps or packet number are different.
On Thu, Jun 8, 2017 at 9:43 PM, Daniel Wagner <wagi(a)monom.org> wrote:
On 06/02/2017 12:04 PM, snorky snorky wrote:
> I have experienced a strange behavior with cellular connections.
> I'm using two SIM from the same provider. One goes in Online state,
> but not the other.
> I have spied the DNS request and no response is received with the
> failing SIM, but a manual nslookup on ipv4.connman.net
> proper DNS (when the connection is up) successfully returns the proper
> IP and a curl on http://ipv4.connman.net/online/status.html
> I'm using 1.30.
> Did someone experience similar behavior? Can it be related to the ISP
> and a delay to wait before doing DNS request?
I had problem getting DHCP response from a ISP via normal DSL modem.
Something on our request seemed to upset the server and no response was
sent. One thing you could try is to record with tcpdump/wireshark the
handshake and post the result (or post a link to the files). Maybe there is
something to see.