From 737cb7ac368040b3ccada20b04a531b8c2dc07bb Mon Sep 17 00:00:00 2001 From: Larry Peterson Date: Thu, 17 Apr 2025 14:32:40 -0700 Subject: [PATCH] override default N3 Signed-off-by: Larry Peterson --- onramp/blueprints.rst | 45 +++++++++++++++++++++---------------------- onramp/ref.rst | 2 +- 2 files changed, 23 insertions(+), 24 deletions(-) diff --git a/onramp/blueprints.rst b/onramp/blueprints.rst index 0ec60c6..ddb632e 100644 --- a/onramp/blueprints.rst +++ b/onramp/blueprints.rst @@ -849,42 +849,41 @@ To deploy the srsRAN blueprint in simulation mode, run the following: $ make srsran-gnb-install $ make srsran-uesim-start -Multihop gNBs -~~~~~~~~~~~~~~~~~~~~~~ - -By default OnRamp uses isolated networks for the N3 (e.g., -192.168.252.x) and N6 (e.g., 192.168.250.x) interfaces. This prevents -gNBs on different subnets or located multiple hops away from -connecting to the UPF on the N3 interface. +Override Default N3 Subnet +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -In order to support such deployments, OnRamp provides an option to -configure N3 from the same subnet as ``core.data_iface``. It can be -enabled by setting setting ``core.upf.multihop_gnb`` to ``true``. +By default, OnRamp manages an isolated subnet (``192.168.252.0/24``) +for the N3 interface. This prevents attaching gNBs on multiple subnets +and/or on subnets that are multiple hops away. This section describes +how to override this setting. It is not technically a self-contained +blueprint, but rather, a configuration option that can be applied to +any of the blueprints defined in this section. -For example, suppose ``core.data_iface`` corresponds to subnet -10.21.61.0/24 and the gNB is on subnet 10.202.1.0/24. Configure the -parameters as follows: +The override requires setting variable ``core.upf.multihop_gnb`` to +``true``. This causes OnRamp to configure the UPF's N3 interface from +the same subnet as ``core.data_iface``. For example, suppose +``core.data_iface`` corresponds to subnet 10.21.61.0/24 and the gNB is +on subnet 10.202.1.0/24. Configure the parameters as follows: .. code-block:: data_iface: ens18 ran_subnet: "10.202.1.0/24" upf: - access_subnet: "10.21.61.1/24" # access subnet & gateway - core_subnet: "192.168.250.1/24" # core subnet & gateway - multihop_gnb: true + access_subnet: "10.21.61.1/24" # access subnet & gateway + core_subnet: "192.168.250.1/24" # core subnet & gateway + multihop_gnb: true # N3 directly reachable via data_iface default_upf: ip: - access: "10.21.61.12" # same subnet as data_iface when multihop_gnb is true + access: "10.21.61.12" # same subnet as data_iface when multihop_gnb=true core: "192.168.250.3" ue_ip_pool: "192.168.100.0/24" -To connect multiple gNBs on different subnets, you must modify -``deps/5gc/roles/core/templates/sdcore-5g-values.yaml`` (if -``core.upf.mode: af_packet``) or -``deps/5gc/roles/core/templates/sdcore-5g-sriov-values.yaml`` (if -``core.upf.mode: dpdk``) to add the necessary routes. For example, if -a second gNB is on 10.203.1.0/24, then add the route as follows: +To connect multiple gNBs on different subnets, you must also modify +the specified values file (e.g., +``deps/5gc/roles/core/templates/sdcore-5g-values.yaml``) to add the +necessary routes. For example, if a second gNB is on 10.203.1.0/24, +then add the route as follows: .. code-block:: diff --git a/onramp/ref.rst b/onramp/ref.rst index 0b7eeb3..b137997 100644 --- a/onramp/ref.rst +++ b/onramp/ref.rst @@ -106,7 +106,7 @@ the list is not comprehensive. - Socket mode for `core.data_iface`; set to `dpdk` to enable DPDK and SR-IOV optimizations. * - `core.upf.multihop_gnb` - `false` - - Routing from `core.data_iface`; set to `true` when external gNB is multiple hops away. + - Override default N3 interface; set to `true` when external gNB is multiple hops away. * - `gnbsim.data_iface` - `ens18` - Network interface used by gNBsim; same as `core.data_iface` when co-located on a single server.