diff options
Diffstat (limited to 'doc/developer')
| -rw-r--r-- | doc/developer/mgmtd-dev.rst | 13 | ||||
| -rw-r--r-- | doc/developer/packaging-redhat.rst | 15 | ||||
| -rw-r--r-- | doc/developer/sbfd.rst | 143 | ||||
| -rw-r--r-- | doc/developer/subdir.am | 1 |
4 files changed, 164 insertions, 8 deletions
diff --git a/doc/developer/mgmtd-dev.rst b/doc/developer/mgmtd-dev.rst index 4c56cadb28..6cbd617f8c 100644 --- a/doc/developer/mgmtd-dev.rst +++ b/doc/developer/mgmtd-dev.rst @@ -160,14 +160,19 @@ Back-End Interface: should be destroyed with a call to `mgmt_be_client_destroy` and to be safe NULL out the global `mgmt_be_client` variable. -#. In ``mgmtd/mgmt_be_adapter.c`` add xpath prefix mappings to a one or both - mapping arrays (``be_client_config_xpaths`` and ``be_client_oper_xpaths``) to - direct ``mgmtd`` to send config and oper-state requests to your daemon. NOTE: - make sure to include library supported xpaths prefixes as well (e.g., +#. In ``mgmtd/mgmt_be_adapter.c`` add xpath prefix mappings to a each of the + mapping arrays (``be_client_config_xpaths``, ``be_client_oper_xpaths``, and + ``be_client_rpc_xpaths``) to direct ``mgmtd`` to send config, oper-state, and + RPC requests to your daemon. + + NOTE: make sure to include library supported xpaths prefixes as well (e.g., "/frr-interface:lib"). A good way to figure these paths out are to look in each of the YANG modules that the daemon uses and include each of their paths in the array. +#. In ``python/xref2vtysh.py`` add ``VTYSH_xxxD`` (for client xxx) to + ``lib/mgmt_be_client.c`` entry in the ``daemon_falgs`` dictionary. + Add YANG and CLI into MGMTD ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ diff --git a/doc/developer/packaging-redhat.rst b/doc/developer/packaging-redhat.rst index 8037873461..277de5d16f 100644 --- a/doc/developer/packaging-redhat.rst +++ b/doc/developer/packaging-redhat.rst @@ -3,7 +3,7 @@ Packaging Red Hat ================= -Tested on CentOS 6, CentOS 7, CentOS 8 and Fedora 24. +Tested on CentOS 6, CentOS 7, Rocky 8 and Fedora 24. 1. On CentOS 6, refer to :ref:`building-centos6` for details on installing sufficiently up-to-date package versions to enable building FRR. @@ -18,14 +18,14 @@ Tested on CentOS 6, CentOS 7, CentOS 8 and Fedora 24. yum install rpm-build net-snmp-devel pam-devel libcap-devel - For CentOS 7 and CentOS 8, the package will be built using python3 + For CentOS 7 and Rocky 8, the package will be built using python3 and requires additional python3 packages:: yum install python3-devel python3-sphinx .. note:: - For CentOS 8 you need to install ``platform-python-devel`` package + For Rocky 8 you need to install ``platform-python-devel`` package to provide ``/usr/bin/pathfix.py``:: yum install platform-python-devel @@ -33,7 +33,7 @@ Tested on CentOS 6, CentOS 7, CentOS 8 and Fedora 24. If ``yum`` is not present on your system, use ``dnf`` instead. - You should enable ``PowerTools`` repo if using CentOS 8 which + You should enable ``PowerTools`` repo if using Rocky 8 which is disabled by default. 4. Checkout FRR:: @@ -88,11 +88,18 @@ Tested on CentOS 6, CentOS 7, CentOS 8 and Fedora 24. %{!?with_watchfrr: %global with_watchfrr 1 } %{!?with_pathd: %global with_pathd 1 } %{!?with_grpc: %global with_grpc 0 } + %{!?with_rpki: %global with_rpki 1 } + %{!?with_docs: %global with_docs 1 } 8. Build the RPM:: rpmbuild --define "_topdir `pwd`/rpmbuild" -ba rpmbuild/SPECS/frr.spec + To override :file:`rpm/SPECS/frr.spec` defaults on the rpmbuild + commandline with: + + rpmbuild --define 'variable value' + If building with RPKI, then download and install the additional RPKI packages from https://ci1.netdef.org/browse/RPKI-RTRLIB/latestSuccessful/artifact diff --git a/doc/developer/sbfd.rst b/doc/developer/sbfd.rst new file mode 100644 index 0000000000..66a3b48dba --- /dev/null +++ b/doc/developer/sbfd.rst @@ -0,0 +1,143 @@ +.. _sbfd: + +**** +SBFD +**** + +:abbr:`SBFD (Seamless Bidirectional Forwarding Detection)` is: + + Seamless Bidirectional Forwarding Detection, a simplified mechanism for using BFD with a large + proportion of negotiation aspects eliminated, thus providing benefits + such as quick provisioning, as well as improved control and + flexibility for network nodes initiating path monitoring. + + -- :rfc:`7880` + +It is described and extended by the following RFCs: + +* :rfc:`7880` +* :rfc:`7881` + +.. _sbfd-sate-machine: + +SBFD state machine +================== + +SBFD takes the same data packet format as BFD, but with a much simpler state machine. +According to RFC7880, SBFD has a stateless SBFDReflector and a stateful SBFDInitiator with the state machine as below: + +:: + + +--+ + ADMIN DOWN, | | + TIMER | V + +------+ UP +------+ + | |-------------------->| |----+ + | DOWN | | UP | | UP + | |<--------------------| |<---+ + +------+ ADMIN DOWN, +------+ + TIMER + + Figure 1: SBFDInitiator Finite State Machine + +.. _sbfd-extention: + +SBFD extension - SRv6 encapsulation +=================================== + +SBFDInitiator periodically send packets to monitor the connection to SBFDReflector. We set up an SBFD connection between the source and the destination node of a path, +with the source node serving as Initiator and the destination node as Reflector. The communicated SBFD packets should also follow every exact hop in the path, +from the source to the destination, which could be achieved by segment routing. This requirement extends the node verification to the path verification. + +.. _sbfd-implement: + +implementation +=============== + +Some considerations when implementing sbfd. + + + +.. _sbfd-implement-coexist: + +SBFD Co-exist with BFD +-------------------------- + +Both SBFD and Classical BFD have their unique discriminator, SBFD can co-exist with BFD since they sharing a same discriminator pool in bfdd. +Also in bfdd SBFD and BFD can share most code logic, SBFD packet and BFD packet are demultiplexed by different discriminators. + + +.. _sbfd-implement-bfdname: + +SBFD name +--------- + +We introduced a bfd-name for every sbfd session. A unique bfd-name can be used to identify a sbfd session quickly. This is quite useful in our Srv6 deployment for path protection case. +A bfd-name is always associated with a TE path, for example if we use the sbfd session to protect the path A-B-D, we would assign the name 'path-a-b-d' or 'a-b-d' to the session. + +Meanwhile bfdd will notify the sbfd status to the Pathd, we should add the bfd-name field in PTM bfd notify message ZEBRA_BFD_DEST_REPLAY: + +:: + + * Message format: + * - header: command, vrf + * - l: interface index + * - c: family + * - AF_INET: + * - 4 bytes: ipv4 + * - AF_INET6: + * - 16 bytes: ipv6 + * - c: prefix length + * - l: bfd status + * - c: family + * - AF_INET: + * - 4 bytes: ipv4 + * - AF_INET6: + * - 16 bytes: ipv6 + * - c: prefix length + * - c: cbit + * - c: bfd name len <---- new field + * - Xbytes: bfd name <---- new field + * + * Commands: ZEBRA_BFD_DEST_REPLAY + * + * q(64), l(32), w(16), c(8) + + + +.. _sbfd-implement-port: + +SBFD UDP port +------------- + +According to RFC7881, SBFD Control packet dst port should be 7784, src port can be any but NOT 7784. In our implementation, the UDP ports in packet are set as: + + +:: + + UDP(sport=4784, dport=7784)/BFD() or UDP(sport=3784, dport=7784)/BFD() + +if "multihop" is specified for sbfd initiator we choose the 4784 as the source port, so the reflected packet will take 4784 as the dst port, this is a local BFD_MULTI_HOP_PORT so the reflected packet can be handled by the existing bfd_recv_cb function. +if "multihop" is not specified for sbfd initiator we choose the 3784 as the source port, this is a local BFD_DEFDESTPORT so the reflected packet can be handled by the existing bfd_recv_cb function. + + +For echo SBFD with SRv6 encapsulation case, we re-use the BFD Echo port, the UDP ports in packet are set as: + +:: + + UDP(sport=3785, dport=3785)/BFD() + + +we choose the 3785 as the source port, so the echo back packet will take 3785 as the dst port, this is a local BFD_DEF_ECHO_PORT so the packet can be handled by the existing bfd_recv_cb function. + + +.. _sbfd-not-implemented: + +Todo list for SBFD +------------------ + + Currently some features are not yet implemented for SBFD, will add it in future: + 1) SBFD in IPv4 only packet + 2) The ADMIN DOWN logic + 3) SBFD echo function in a initiator session + 4) SBFD over MPLS diff --git a/doc/developer/subdir.am b/doc/developer/subdir.am index bdf93a05c1..9f6986cd33 100644 --- a/doc/developer/subdir.am +++ b/doc/developer/subdir.am @@ -83,6 +83,7 @@ dev_RSTFILES = \ doc/developer/northbound/transactional-cli.rst \ doc/developer/northbound/yang-module-translator.rst \ doc/developer/northbound/yang-tools.rst \ + doc/developer/sbfd.rst \ # end EXTRA_DIST += \ |