After some debugging I found that the intermittent data loss was caused by the GSN not properly reacting to Error Indication packets.
From GGSN:
<0002> ggsn.c:809 PDP(450091417013617:5): Packet received on APN(internet): forwarding to tun apn0 <000d> gtp.c:2681 Packet from 192.168.27.49:2152, length: 24 content: 32 1a 00 10 00 00 00 00 40 8e 00 00 10 00 00 00 05 85 00 04 c0 a8 1b 31 : Received Error Indication <0002> ggsn.c:372 PDP(450091417013617:5): Deleting PDP context <000d> pdp.c:255 Begin pdp_tiddel tid = 5716310714190054 <000d> pdp.c:262 End pdp_tiddel: PDP found When the GGSN receives an error indication, isnt' it supposed to acknowlege the SGSN and attempt to reinitialize the connection? In my case the GGSN simply deleted the PDP context locally and both SGSN and GGSN gets flooded by unknown PDP context error, while the phone keeps trying to transmit data. Tested on lastest git version and lastest release version: osmo-sgsn 1.3.0, osmo-ggsn 1.2.1 Regards, Pierre
Hi, please open a ticket in redmine with: * information about osmocom versions used (and commit hash if you are not running a release). * Explanation about what you see * Expected behavior (if possible linked to some spec section) * pcap trace of what you see IIRC it's good behavior to drop the connections when you receive an Error Indication with the reset counter incremented. -- - Pau Espin Pedrol <pespin@sysmocom.de> http://www.sysmocom.de/ ======================================================================= * sysmocom - systems for mobile communications GmbH * Alt-Moabit 93 * 10559 Berlin, Germany * Sitz / Registered office: Berlin, HRB 134158 B * Geschaeftsfuehrer / Managing Director: Harald Welte
Lol, what a synchronicity we got :-D 12.11.18 10:34, Pau Espin Pedrol пишет:
Hi,
please open a ticket in redmine with: * information about osmocom versions used (and commit hash if you are not running a release). * Explanation about what you see * Expected behavior (if possible linked to some spec section) * pcap trace of what you see
IIRC it's good behavior to drop the connections when you receive an Error Indication with the reset counter incremented.
-- - Max Suraev <msuraev@sysmocom.de> http://www.sysmocom.de/ ======================================================================= * sysmocom - systems for mobile communications GmbH * Alt-Moabit 93 * 10559 Berlin, Germany * Sitz / Registered office: Berlin, HRB 134158 B * Geschaeftsfuehrer / Managing Directors: Harald Welte
Hi! Thanks for your feedback. Seems like a bug indeed. Could you please make a ticket via https://osmocom.org/projects/openggsn/issues/new (registration sould be quick and easy if you don't have one yet). Would be great if you could share more details in the ticket as well: - your configs - how to trigger this error indication reliably - any spec. reference for proper behavior - whatever else you think is relevant 11.11.18 07:00, Pierre Kim пишет:
After some debugging I found that the intermittent data loss was caused by the GSN not properly reacting to Error Indication packets.
From GGSN:
<0002> ggsn.c:809 PDP(450091417013617:5): Packet received on APN(internet): forwarding to tun apn0 <000d> gtp.c:2681 Packet from 192.168.27.49:2152, length: 24 content: 32 1a 00 10 00 00 00 00 40 8e 00 00 10 00 00 00 05 85 00 04 c0 a8 1b 31 : Received Error Indication <0002> ggsn.c:372 PDP(450091417013617:5): Deleting PDP context <000d> pdp.c:255 Begin pdp_tiddel tid = 5716310714190054 <000d> pdp.c:262 End pdp_tiddel: PDP found
When the GGSN receives an error indication, isnt' it supposed to acknowlege the SGSN and attempt to reinitialize the connection? In my case the GGSN simply deleted the PDP context locally and both SGSN and GGSN gets flooded by unknown PDP context error, while the phone keeps trying to transmit data.
Tested on lastest git version and lastest release version: osmo-sgsn 1.3.0, osmo-ggsn 1.2.1
Regards,
Pierre
-- - Max Suraev <msuraev@sysmocom.de> http://www.sysmocom.de/ ======================================================================= * sysmocom - systems for mobile communications GmbH * Alt-Moabit 93 * 10559 Berlin, Germany * Sitz / Registered office: Berlin, HRB 134158 B * Geschaeftsfuehrer / Managing Directors: Harald Welte
participants (3)
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Max -
Pau Espin Pedrol -
Pierre Kim