* Initial metrics support based on Prometheus
This commit introduces initial support for metrics in open5gs.
The metrics code is added as libogsmetrics (lib/metrics/), with a well
defined opaque API to manage different types of metrics, allowing for
different implementations for different technologies to scrap the
metrics (placed as lib/metrics/<impl>/. The implementation is right now
selected at build time, in order to be able to opt-out the related dependencies
for users not interested in the features. 2 implementations are already
provided in this commit to start with:
* void: Default implementation. Empty stubs, acts as a NOOP.
* prometheus: open5gs processes become Prometheus servers, offering
states through an http server to the Prometheus scrappers. Relies on
libprom (prometheus-client-ci [1] project) to track the metrics and format
them during export, and libmicrohttpd to make the export possible through
HTTP.
[1] https://github.com/digitalocean/prometheus-client-c
The prometheus-client-c is not well maintained nowadays in upstream, and
furthermore it uses a quite peculiar mixture of build systems (autolib
on the main dir, cmake for libprom in a subdir). This makes it difficult
to have it widely available in distros, and difficult to find it if it
is installed in the system. Hence, the best is to include it as a
meson subproject like we already do for freeDiameter. An open5gs fork is
requried in order to have an extra patch adding a top-level
CMakeList.txt in order to be able to includ eit from open5gs's meson
build. Furthermore, this allows adding bugfixes to the subproject if any
are found in the future.
* [SMF] Initial metrics support
* [SMF] Add metrics at gtp_node level
* docs: Add tutorial documenting metrics with Prometheus
The use of the Gy interface (SMF acting as CTF towards an OCS node) is
mandated through configuration file. Default value "enable: auto" will
only make use of it in case a Diameter peer announcing support for the
Credit-Control Application is found.
Upon subscriber session creation, and after auth check over Gx, the SMF
will create a Gy session with the OCS and only after that step the SMF
will accept the session back to the subscriber.
The OCS may then grant some traffic volumes/time and ask to be notified
back with updated measurements.
In order to get the measurements, the SMF relies on PFCP URR configured
to the UPF through Session Repoort Request messages.
When closing the subscriber session, the SMF will also terminate the Gy
session at the OCS.
So far only some specifics parts of the Gy interface as well as the PFCP
side are implemented. Those should be enough to at least have
volume/time thresholds granted by the OCS, which then will be able to
track subsriber resource use.
This patch doesn't implement the OCS side of the Gy interface, that's
left as a future exercise. The interface was tested using an OCS
emulator implemented in TTCN-3 [1]
[1] https://cgit.osmocom.org/osmo-ttcn3-hacks/
* Fix conversion from IPFilterRule to packet filter
As per 3GPP TS 24.008, following Packet filter component type identifier
are not supported on the LTE pre release-11 UEs:
IPv4 local address type
IPv6 remote address/prefix length type
IPv6 local address/prefix length type
And,
IPv6 remote address/prefix length type and
IPv6 local address/prefix length type shall be used when both MS and
Network support Local Address in TFTs.
This commit add logic to omit adding local address in packet filters
for compatibility with pre-release LTE 11 devices. The following parameter
could be used to toggle omit/no to omit behavior.
parameter:
no_ipv4v6_local_addr_in_packet_filter: <true/false>
* Remove logic of supporting pre-release LTE 11 devices in PCRF
* [configs] Remove requires systemd-networkd dep from smfd service
The smf no longer has (never had?) a dependency on systemd-networkd,
and can start and remain operational without systemd-networkd
specifically running.
* [configs] Relax upf dependency on systemd-networkd
The upf relies on systemd-networkd to create the ogstun interface, but
does not communicate with it at runtime. It currently has a "Requires"
dependency specified, which means that the upf will be stopped if
systemd-networkd is ever stopped. Since the upf doesn't actually care
if systemd-networkd is later stopped after ogstun is created, it can
use the weaker "Wants" dependency type, which allows it to keep
running even if systemd-networkd were to be stopped.
Regardless, since it does rely on systemd-networkd specifically to
create the ogstun interface, it should sequence itself "After"
systemd-networkd has been started.
Since the true dependency is ogstun, not systemd-networkd, a cleaner
approach would depend on the specific tunnel device being
available. Systemd exposes this information via device units, but I'm
not sure if they are always consistently named across platforms.
* [configs] Do not require ogstun for system online
Systemd-networkd will wait for all managed interfaces to be configured
before determining the system is online. Since the ogstun and upf are
more logically an application rather than a system networking service,
don't wait for them to be configured by default.
This breaks the circular dependency between the userspace cellular
core network services and the system's network, which will allow the
cellular core network services to sequence themselves cleanly after
the system's network is up and configured.
* [configs] Sequence network-dependent units after network-online
Since open5gs targets platforms with both ifupdown (debian) and
systemd-networkd (Ubuntu) as core networking providers, this commit
sequences network-dependent core network components after the generic
network-online.target instead of one of the specific provider
targets. This allows the core network to operate correctly with both
systemd-networkd and ifupdown (networking), and fixes the issue
observed in https://github.com/open5gs/open5gs/issues/826 where some
platforms may fail to start cleanly.
* Preserve local port in Rx flow-description
In contnuation to support for calling in pre-rel. LTE 11 devices
, rather than removing the local IP addr field and local port remove
only the IP addr field
* tft: Set precedence considering exisiting TFTs in all bearers of a DNN
The configuration has changed. PFCP node rr=0 is removed as shown below.
sgwc:
pfcp
rr: 0 <-- Removed
Introduced a new configuration method for SMF/SGW-C
parameter:
no_pfcp_rr_select: true
By default, PFCP round robin selection is allowed.
The above parameters prohibit selecting PFCP in a round robin manner.
If parameter.ignore_requsted_nssai is true,
AMF will ignore the UE Requested NSSAI and create an allowed-NSSAI
based on the Default S-NSSAI in the Subscription DB.
* AAR Media-Sub-Component modification for more UEs support
* Introduce parameter for legacy support for pre-release LTE 11 devices to do calling
IE (IPV4-local-addr field ) is not supported on
the LTE pre release-11 UEs. In order for the call
to work the local address in packet filter must
be replaced by any.
Parameter: no_ipv4v6_local_addr_in_packet_filter
Alexander Couzens
Carlos Giraldo
Pau Espin
Sukchan Lee
EugeneBogush
Supreeth Herle
Matthew Johnson
Julian Lemmerich