23 Nov
2017
23 Nov
'17
12:02 p.m.
Hi guys,
I'm using libgtpnl tools (gtp-link, gtp-tunnel) to setup a tunnel in my
local
machines. I was able to setup gtp link to 2152 port as well as gtp tunnel.
I have pre-recorded GTP packets with correct teid and IP address as well
as chksum and port to send to 2152. However I can not see any packets
in gtp link device when using tcpdump.
By add some messages in gtp module, I notice that the function
gtp1u_udp_encap_recv in gtp.c kernel file was never been called if I send
packet with GTP headers. However, that function is called if I send normal
UDP packet without GTP header.
Note that I'm using Ubuntu 14.04 with kernel 4.8.0 lowlatency, the tunnel
is on a VM created by Virtualbox using virtio network driver. Any
suggestions
on how to debug/solve this problem?
Many thanks in advances.
Best regards
Cong.
23 Nov
23 Nov
2:30 p.m.
hi Cong,
it would be very useful if you could give a description of what exactly
your are trying to achieve, using which particular versions of which software.
The kernel GTP module is known-working and has been verified with both
OpenGGSN and OsmoSGSN. There are also other users such as OpenAirInterface
as well as (as far as I know) ergw. It might be easiest to simply use
one of those programs to understnd how the kernel GTP-U driver is used.
Also, if you want us to be able to help you, please always include the detailed
copy+paste output of the related commands and tools, e.g. the exact gtp-link
and gtp-tunnel commands you have been using.
--
- Harald Welte <laforge(a)gnumonks.org> http://laforge.gnumonks.org/
============================================================================
"Privacy in residential applications is a desirable marketing option."
(ETSI EN 300 175-7 Ch. A6)
24 Nov
24 Nov
5:52 a.m.
Hi Harald and Firat,
Thank you very much for your reply. Sorry for not provide detail information
when asking question.
Lucky me, I am able to solve my problem now. It's because of wrong MAC
address in packets that cause gtp device unable to receive. Stupid mistake.
Still, I post it here just in case it can help other newbies like me.
Thanks and best regards
Cong
On 11/23/2017 08:30 PM, Harald Welte wrote:
hi Cong,
it would be very useful if you could give a description of what exactly
your are trying to achieve, using which particular versions of which software.
The kernel GTP module is known-working and has been verified with both
OpenGGSN and OsmoSGSN. There are also other users such as OpenAirInterface
as well as (as far as I know) ergw. It might be easiest to simply use
one of those programs to understnd how the kernel GTP-U driver is used.
Also, if you want us to be able to help you, please always include the detailed
copy+paste output of the related commands and tools, e.g. the exact gtp-link
and gtp-tunnel commands you have been using.
2368
days inactive
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days old
osmocom-net-gprs@lists.osmocom.org
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participants (2)
-
congnt -
Harald Welte