OsmoGGSN » History » Revision 16
Revision 15 (wirelesss, 12/27/2016 09:37 AM) → Revision 16/34 (wirelesss, 12/30/2016 10:06 AM)
h1. [[OpenGGSN]] [[OpenGGSN]] is an implementation of the Gateway GPRS Support Node ("GGSN":http://en.wikipedia.org/wiki/GGSN) element in the GPRS core network. [[OpenGGSN]] was developed in 2002 to 2004 by Mondru AB and was abandoned for some years before adopted by the Osmocom project around 2010. h2. Source Code / git repository The source code is maintained in the osmcoom git at http://git.osmocom.org/openggsn/ h2. Binary packages OpenGGSN packages are created as part of the Osmocom nightly debian builds, see [[cellular-infrastructure:NightlyBuilds]] h2. Support / mailing lists Please direct any questions regarding use, configuration or development of OpenGGSN to the osmocom-net-gprs@lists.osmocom.org mailing list, to which you can subscribe at https://lists.osmocom.org/mailman/listinfo/osmocom-net-gprs h2. Building OpenGGSN with kernel which has GTP-U support It is expected that complete openbsc project and dependencies are pre-installed. Check if package @libc-ares-dev@ is installed and if not please add it. Ubuntu 16.10, kernel 4.8.0-30-generic is used. * Installing dependencies and build library @libgtpnl@ You can install those packages with: <pre> sudo apt install libtalloc-dev libpcsclite libmnl-dev </pre> Please follow instructions provided at [[cellular-infrastructure:Build from source]] in order to install following library and projects : Information about dependencies between Osmocom projects is given at the above link: * libgtpnl <pre> sudo make install sudo ldconfig </pre> * libosmocore * openggsn <pre> ./configure --enable-gtp-linux make sudo make install sudo ldconfig </pre> Following message is shown at end of the command: @ ./configure --enable-gtp-linux@ <pre> openggsn Configuration: GTP Linux kernel support: yes </pre> This means that appropriate header files are available. h2. Using OpenGGSN with kernel which has GTP-U support In order to find out whether gtp.ko module is available we can enter following command: <pre> find /lib/modules/`uname -r` -name gtp.ko </pre> Output below shows that gtp.ko module is present <pre> /lib/modules/4.8.0-30-generic/kernel/drivers/net/gtp.ko </pre> We are loading module gtp from kernel issuing command: command <pre>sudo modprobe gtp </pre> when you enter: command: <pre> lsmod | grep gtp </pre> give us information about gtp and related udp tunnel: <pre> gtp 28672 0 udp_tunnel 16384 1 gtp </pre> Some helpful tools are available in: @libgtpnl/tools@ you can get more details about gtp-tunnel, entering command from the OpenGGSN shell: <pre> sudo ./gtp-tunnel list </pre> Output will be similar to: <pre> version 1 tei 1/0 ms_addr 192.168.0.2 sgsn_addr 127.0.0.2 </pre> Furthermore we can use: <pre> sudo starce ggsn --gtp-linux -c ggsn.conf -f -d </pre> to determine if Ubuntu 16.10, kernel 4.8.0-30 is in use. Next two cases shall be considered as an indication whether gtp kernel module is active: ** If gtp kernel module is active then we can see the strace output just when PDP context activation or deactivation is done. ** If gtp kernel module is not active then we can see the strace output constantly running on the screen. Note: OpenGGSN is started by: <pre> sudo ggsn --gtp-linux -c ggsn.conf -f -d </pre> -d option is useful for debugging purposes. Related output should be similar to the one shown below: <pre> conf: ggsn.conf fg: 1 debug: 1 qos: 0x0b921f apn: internet net: 192.168.0.0/24 pidfile: /var/run/ggsn.pid statedir: /var/lib/ggsn/ gtp_linux: 1 timelimit: 0 cmdline_parser_configfile listen: 127.0.0.1 conf: ggsn.conf fg: 1 debug: 1 qos: 0x0b921f apn: internet net: 192.168.0.0/24 pidfile: /var/run/ggsn.pid statedir: /var/lib/ggsn/ gtp-linux: 1 timelimit: 0 <000c> gtp.c:701 GTP: gtp_newgsn() started <0002> gtp-kernel.c:123 Using the GTP kernel mode (genl ID is 27) <0002> gtp-kernel.c:156 GTP kernel configured <000b> control_if.c:693 CTRL at 127.0.0.1 4257 </pre> osmosgsn can be started with: <pre> sudo osmo-sgsn -c sgsn.cfg </pre> - d option is also available ins osmo-sgsn command. Additional information related to setup of openbsc and GPRS setup is available [[cellular-infrastructure:OpenBSC GPRS]] For clarity purposes configuration files of openbsc, OpenGGSN, osmosgsn and sysmoBTS are added.