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Zebra

zebra is an IP routing manager. It provides kernel routing table updates, interface lookups, and redistribution of routes between different routing protocols.

Invoking zebra

Besides the common invocation options (:ref:`common-invocation-options`), the zebra specific invocation options are listed below.

.. program:: zebra

.. option:: -b, --batch

   Runs in batch mode. *zebra* parses configuration file and terminates
   immediately.

.. option:: -K TIME, --graceful_restart TIME

   If this option is specified, the graceful restart time is TIME seconds.
   Zebra, when started, will read in routes.  Those routes that Zebra
   identifies that it was the originator of will be swept in TIME seconds.
   If no time is specified then we will sweep those routes immediately.

.. option:: -r, --retain

   When program terminates, do not flush routes installed by *zebra* from the
   kernel.

.. option:: -e X, --ecmp X

   Run zebra with a limited ecmp ability compared to what it is compiled to.
   If you are running zebra on hardware limited functionality you can
   force zebra to limit the maximum ecmp allowed to X.  This number
   is bounded by what you compiled FRR with as the maximum number.

.. option:: -n, --vrfwnetns

   When *Zebra* starts with this option, the VRF backend is based on Linux
   network namespaces. That implies that all network namespaces discovered by
   ZEBRA will create an associated VRF. The other daemons will operate on the VRF
   VRF defined by *Zebra*, as usual.

   .. seealso:: :ref:`zebra-vrf`

.. option:: -o, --vrfdefaultname

   When *Zebra* starts with this option, the default VRF name is changed to the
   parameter.

   .. seealso:: :ref:`zebra-vrf`

.. option:: -z <path_to_socket>, --socket <path_to_socket>

   If this option is supplied on the cli, the path to the zebra
   control socket(zapi), is used.  This option overrides a -N <namespace>
   option if handed to it on the cli.

.. option:: --v6-rr-semantics

   The linux kernel is receiving the ability to use the same route
   replacement semantics for v6 that v4 uses.  If you are using a
   kernel that supports this functionality then run *Zebra* with this
   option and we will use Route Replace Semantics instead of delete
   than add.

.. option:: --asic-offload [notify_on_offload|notify_on_ack]

   The linux kernel has the ability to use asic-offload ( see switchdev
   development ).  When the operator knows that FRR will be working in
   this way, allow them to specify this with FRR.  At this point this
   code only supports asynchronous notification of the offload state.
   In other words the initial ACK received for linux kernel installation
   does not give zebra any data about what the state of the offload
   is.  This option takes the optional paramegers notify_on_offload
   or notify_on_ack.  This signals to zebra to notify upper level
   protocols about route installation/update on ack received from
   the linux kernel or from offload notification.

Configuration Addresses behaviour

At startup, Zebra will first discover the underlying networking objects from the operating system. This includes interfaces, addresses of interfaces, static routes, etc. Then, it will read the configuration file, including its own interface addresses, static routes, etc. All this information comprises the operational context from Zebra. But configuration context from Zebra will remain the same as the one from :file:`zebra.conf` config file. As an example, executing the following :clicmd:`show running-config` will reflect what was in :file:`zebra.conf`. In a similar way, networking objects that are configured outside of the Zebra like iproute2 will not impact the configuration context from Zebra. This behaviour permits you to continue saving your own config file, and decide what is really to be pushed on the config file, and what is dependent on the underlying system. Note that inversely, from Zebra, you will not be able to delete networking objects that were previously configured outside of Zebra.

Interface Commands

Standard Commands

.. clicmd:: interface IFNAME


.. clicmd:: interface IFNAME vrf VRF


.. clicmd:: shutdown


   Up or down the current interface.


.. clicmd:: ip address ADDRESS/PREFIX

.. clicmd:: ipv6 address ADDRESS/PREFIX



   Set the IPv4 or IPv6 address/prefix for the interface.


.. clicmd:: ip address LOCAL-ADDR peer PEER-ADDR/PREFIX


   Configure an IPv4 Point-to-Point address on the interface. (The concept of
   PtP addressing does not exist for IPv6.)

   `local-addr` has no subnet mask since the local side in PtP addressing is
   always a single (/32) address. `peer-addr/prefix` can be an arbitrary subnet
   behind the other end of the link (or even on the link in Point-to-Multipoint
   setups), though generally /32s are used.


.. clicmd:: description DESCRIPTION ...

   Set description for the interface.


.. clicmd:: multicast


   Enable or disables multicast flag for the interface.


.. clicmd:: bandwidth (1-10000000)


   Set bandwidth value of the interface in kilobits/sec. This is for
   calculating OSPF cost. This command does not affect the actual device
   configuration.


.. clicmd:: link-detect


   Enable/disable link-detect on platforms which support this. Currently only
   Linux, and only where network interface drivers support reporting
   link-state via the ``IFF_RUNNING`` flag.

   In FRR, link-detect is on by default.

Link Parameters Commands

Note

At this time, FRR offers partial support for some of the routing protocol extensions that can be used with MPLS-TE. FRR does not support a complete RSVP-TE solution currently.

.. clicmd:: link-params


   Enter into the link parameters sub node. At least 'enable' must be
   set to activate the link parameters, and consequently routing
   information that could be used as part of Traffic Engineering on
   this interface. MPLS-TE must be enable at the OSPF
   (:ref:`ospf-traffic-engineering`) or ISIS
   (:ref:`isis-traffic-engineering`) router level in complement to
   this.  Disable link parameters for this interface.

   Under link parameter statement, the following commands set the different TE values:

.. clicmd:: link-params [enable]

   Enable link parameters for this interface.

.. clicmd:: link-params [metric (0-4294967295)]

.. clicmd:: link-params max-bw BANDWIDTH

.. clicmd:: link-params max-rsv-bw BANDWIDTH

.. clicmd:: link-params unrsv-bw (0-7) BANDWIDTH

.. clicmd:: link-params admin-grp BANDWIDTH

   These commands specifies the Traffic Engineering parameters of the interface
   in conformity to RFC3630 (OSPF) or RFC5305 (ISIS).  There are respectively
   the TE Metric (different from the OSPF or ISIS metric), Maximum Bandwidth
   (interface speed by default), Maximum Reservable Bandwidth, Unreserved
   Bandwidth for each 0-7 priority and Admin Group (ISIS) or Resource
   Class/Color (OSPF).

   Note that BANDIWDTH is specified in IEEE floating point format and express
   in Bytes/second.

.. clicmd:: link-param delay (0-16777215) [min (0-16777215) | max (0-16777215)]

.. clicmd:: link-param delay-variation (0-16777215)

.. clicmd:: link-param packet-loss PERCENTAGE

.. clicmd:: link-param res-bw BANDWIDTH

.. clicmd:: link-param ava-bw BANDWIDTH

.. clicmd:: link-param use-bw BANDWIDTH

   These command specifies additional Traffic Engineering parameters of the
   interface in conformity to draft-ietf-ospf-te-metrics-extension-05.txt and
   draft-ietf-isis-te-metrics-extension-03.txt. There are respectively the
   delay, jitter, loss, available bandwidth, reservable bandwidth and utilized
   bandwidth.

   Note that BANDWIDTH is specified in IEEE floating point format and express
   in Bytes/second.  Delays and delay variation are express in micro-second
   (µs). Loss is specified in PERCENTAGE ranging from 0 to 50.331642% by step
   of 0.000003.

.. clicmd:: link-param neighbor <A.B.C.D> as (0-65535)

.. clicmd:: link-param no neighbor

   Specifies the remote ASBR IP address and Autonomous System (AS) number
   for InterASv2 link in OSPF (RFC5392).  Note that this option is not yet
   supported for ISIS (RFC5316).

.. clicmd:: ip nht resolve-via-default

   Allows nexthop tracking to resolve via the default route. This is useful
   when e.g. you want to allow BGP to peer across the default route.

Administrative Distance

Administrative distance allows FRR to make decisions about what routes should be installed in the rib based upon the originating protocol. The lowest Admin Distance is the route selected. This is purely a subjective decision about ordering and care has been taken to choose the same distances that other routing suites have choosen.

Protocol Distance
System 0
Kernel 0
Connect 0
Static 1
NHRP 10
EBGP 20
EIGRP 90
BABEL 100
OSPF 110
ISIS 115
OPENFABRIC 115
RIP 120
Table 150
SHARP 150
IBGP 200
PBR 200

An admin distance of 255 indicates to Zebra that the route should not be installed into the Data Plane. Additionally routes with an admin distance of 255 will not be redistributed.

Zebra does treat Kernel routes as special case for the purposes of Admin Distance. Upon learning about a route that is not originated by FRR we read the metric value as a uint32_t. The top byte of the value is interpreted as the Administrative Distance and the low three bytes are read in as the metric. This special case is to facilitate VRF default routes.

Route Replace Semantics

When using the Linux Kernel as a forwarding plane, routes are installed with a metric of 20 to the kernel. Please note that the kernel's metric value bears no resemblence to FRR's RIB metric or admin distance. It merely is a way for the Linux Kernel to decide which route to use if it has multiple routes for the same prefix from multiple sources. An example here would be if someone else was running another routing suite besides FRR at the same time, the kernel must choose what route to use to forward on. FRR choose the value of 20 because of two reasons. FRR wanted a value small enough to be choosen but large enough that the operator could allow route prioritization by the kernel when multiple routing suites are being run and FRR wanted to take advantage of Route Replace semantics that the linux kernel offers. In order for Route Replacement semantics to work FRR must use the same metric when issuing the replace command. Currently FRR only supports Route Replace semantics using the Linux Kernel.

Virtual Routing and Forwarding

FRR supports :abbr:`VRF (Virtual Routing and Forwarding)`. VRF is a way to separate networking contexts on the same machine. Those networking contexts are associated with separate interfaces, thus making it possible to associate one interface with a specific VRF.

VRF can be used, for example, when instantiating per enterprise networking services, without having to instantiate the physical host machine or the routing management daemons for each enterprise. As a result, interfaces are separate for each set of VRF, and routing daemons can have their own context for each VRF.

This conceptual view introduces the Default VRF case. If the user does not configure any specific VRF, then by default, FRR uses the Default VRF.

Configuring VRF networking contexts can be done in various ways on FRR. The VRF interfaces can be configured by entering in interface configuration mode :clicmd:`interface IFNAME vrf VRF`.

A VRF backend mode is chosen when running Zebra.

If no option is chosen, then the Linux VRF implementation as references in https://www.kernel.org/doc/Documentation/networking/vrf.txt will be mapped over the Zebra VRF. The routing table associated to that VRF is a Linux table identifier located in the same Linux network namespace where Zebra started. Please note when using the Linux VRF routing table it is expected that a default Kernel route will be installed that has a metric as outlined in the www.kernel.org doc above. The Linux Kernel does table lookup via a combination of rule application of the rule table and then route lookup of the specified table. If no route match is found then the next applicable rule is applied to find the next route table to use to look for a route match. As such if your VRF table does not have a default blackhole route with a high metric VRF route lookup will leave the table specified by the VRF, which is undesirable.

If the :option:`-n` option is chosen, then the Linux network namespace will be mapped over the Zebra VRF. That implies that Zebra is able to configure several Linux network namespaces. The routing table associated to that VRF is the whole routing tables located in that namespace. For instance, this mode matches OpenStack Network Namespaces. It matches also OpenFastPath. The default behavior remains Linux VRF which is supported by the Linux kernel community, see https://www.kernel.org/doc/Documentation/networking/vrf.txt.

Because of that difference, there are some subtle differences when running some commands in relationship to VRF. Here is an extract of some of those commands:

.. clicmd:: vrf VRF

   This command is available on configuration mode. By default, above command
   permits accessing the VRF configuration mode. This mode is available for
   both VRFs. It is to be noted that *Zebra* does not create Linux VRF.
   The network administrator can however decide to provision this command in
   configuration file to provide more clarity about the intended configuration.

.. clicmd:: netns NAMESPACE

   This command is based on VRF configuration mode. This command is available
   when *Zebra* is run in :option:`-n` mode. This command reflects which *Linux
   network namespace* is to be mapped with *Zebra* VRF. It is to be noted that
   *Zebra* creates and detects added/suppressed VRFs from the Linux environment
   (in fact, those managed with iproute2). The network administrator can however
   decide to provision this command in configuration file to provide more clarity
   about the intended configuration.

.. clicmd:: show ip route vrf VRF

   The show command permits dumping the routing table associated to the VRF. If
   *Zebra* is launched with default settings, this will be the ``TABLENO`` of
   the VRF configured on the kernel, thanks to information provided in
   https://www.kernel.org/doc/Documentation/networking/vrf.txt. If *Zebra* is
   launched with :option:`-n` option, this will be the default routing table of
   the *Linux network namespace* ``VRF``.

.. clicmd:: show ip route vrf VRF table TABLENO

   The show command is only available with :option:`-n` option. This command
   will dump the routing table ``TABLENO`` of the *Linux network namespace*
   ``VRF``.

.. clicmd:: show ip route vrf VRF tables

   This command will dump the routing tables within the vrf scope. If `vrf all`
   is executed, all routing tables will be dumped.

.. clicmd:: show <ip|ipv6> route summary [vrf VRF] [table TABLENO] [prefix]

   This command will dump a summary output of the specified VRF and TABLENO
   combination.  If neither VRF or TABLENO is specified FRR defaults to
   the default vrf and default table.  If prefix is specified dump the
   number of prefix routes.

By using the :option:`-n` option, the Linux network namespace will be mapped over the Zebra VRF. One nice feature that is possible by handling Linux network namespace is the ability to name default VRF. At startup, Zebra discovers the available Linux network namespace by parsing folder /var/run/netns. Each file stands for a Linux network namespace, but not all Linux network namespaces are available under that folder. This is the case for default VRF. It is possible to name the default VRF, by creating a file, by executing following commands.

touch /var/run/netns/vrf0
mount --bind /proc/self/ns/net /var/run/netns/vrf0

Above command illustrates what happens when the default VRF is visible under var/run/netns/. Here, the default VRF file is vrf0. At startup, FRR detects the presence of that file. It detects that the file statistics information matches the same file statistics information as /proc/self/ns/net ( through stat() function). As statistics information matches, then vrf0 stands for the new default namespace name. Consequently, the VRF naming Default will be overridden by the new discovered namespace name vrf0.

For those who don't use VRF backend with Linux network namespace, it is possible to statically configure and recompile FRR. It is possible to choose an alternate name for default VRF. Then, the default VRF naming will automatically be updated with the new name. To illustrate, if you want to recompile with global value, use the following command:

./configure --with-defaultvrfname=global

MPLS Commands

You can configure static mpls entries in zebra. Basically, handling MPLS consists of popping, swapping or pushing labels to IP packets.

MPLS Acronyms

:abbr:`LSR (Labeled Switch Router)`
Networking devices handling labels used to forward traffic between and through them.
:abbr:`LER (Labeled Edge Router)`
A Labeled edge router is located at the edge of an MPLS network, generally between an IP network and an MPLS network.

MPLS Push Action

The push action is generally used for LER devices, which want to encapsulate all traffic for a wished destination into an MPLS label. This action is stored in routing entry, and can be configured like a route:

.. clicmd:: ip route NETWORK MASK GATEWAY|INTERFACE label LABEL

   NETWORK and MASK stand for the IP prefix entry to be added as static
   route entry.
   GATEWAY is the gateway IP address to reach, in order to reach the prefix.
   INTERFACE is the interface behind which the prefix is located.
   LABEL is the MPLS label to use to reach the prefix abovementioned.

   You can check that the static entry is stored in the zebra RIB database, by
   looking at the presence of the entry.

   ::

      zebra(configure)# ip route 1.1.1.1/32 10.0.1.1 label 777
      zebra# show ip route
      Codes: K - kernel route, C - connected, S - static, R - RIP,
      O - OSPF, I - IS-IS, B - BGP, E - EIGRP, N - NHRP,
      T - Table, v - VNC, V - VNC-Direct, A - Babel, D - SHARP,
      F - PBR,
      > - selected route, * - FIB route

      S>* 1.1.1.1/32 [1/0] via 10.0.1.1, r2-eth0, label 777, 00:39:42

MPLS Swap and Pop Action

The swap action is generally used for LSR devices, which swap a packet with a label, with an other label. The Pop action is used on LER devices, at the termination of the MPLS traffic; this is used to remove MPLS header.

.. clicmd:: mpls lsp INCOMING_LABEL GATEWAY OUTGOING_LABEL|explicit-null|implicit-null

   INCOMING_LABEL and OUTGOING_LABEL are MPLS labels with values ranging from 16
   to 1048575.
   GATEWAY is the gateway IP address where to send MPLS packet.
   The outgoing label can either be a value or have an explicit-null label header. This
   specific header can be read by IP devices. The incoming label can also be removed; in
   that case the implicit-null keyword is used, and the outgoing packet emitted is an IP
   packet without MPLS header.

You can check that the MPLS actions are stored in the zebra MPLS table, by looking at the presence of the entry.

.. clicmd:: show mpls table

zebra(configure)# mpls lsp 18 10.125.0.2 implicit-null
zebra(configure)# mpls lsp 19 10.125.0.2 20
zebra(configure)# mpls lsp 21 10.125.0.2 explicit-null
zebra# show mpls table
Inbound                            Outbound
Label     Type          Nexthop     Label
--------  -------  ---------------  --------
18     Static       10.125.0.2  implicit-null
19     Static       10.125.0.2  20
21     Static       10.125.0.2  IPv4 Explicit Null

Multicast RIB Commands

The Multicast RIB provides a separate table of unicast destinations which is used for Multicast Reverse Path Forwarding decisions. It is used with a multicast source's IP address, hence contains not multicast group addresses but unicast addresses.

This table is fully separate from the default unicast table. However, RPF lookup can include the unicast table.

WARNING: RPF lookup results are non-responsive in this version of FRR, i.e. multicast routing does not actively react to changes in underlying unicast topology!

.. clicmd:: ip multicast rpf-lookup-mode MODE


   MODE sets the method used to perform RPF lookups. Supported modes:

   urib-only
      Performs the lookup on the Unicast RIB. The Multicast RIB is never used.

   mrib-only
      Performs the lookup on the Multicast RIB. The Unicast RIB is never used.

   mrib-then-urib
      Tries to perform the lookup on the Multicast RIB. If any route is found,
      that route is used. Otherwise, the Unicast RIB is tried.

   lower-distance
      Performs a lookup on the Multicast RIB and Unicast RIB each. The result
      with the lower administrative distance is used;  if they're equal, the
      Multicast RIB takes precedence.

   longer-prefix
      Performs a lookup on the Multicast RIB and Unicast RIB each. The result
      with the longer prefix length is used;  if they're equal, the
      Multicast RIB takes precedence.

      The `mrib-then-urib` setting is the default behavior if nothing is
      configured. If this is the desired behavior, it should be explicitly
      configured to make the configuration immune against possible changes in
      what the default behavior is.

Warning

Unreachable routes do not receive special treatment and do not cause fallback to a second lookup.

.. clicmd:: show ip rpf ADDR

   Performs a Multicast RPF lookup, as configured with ``ip multicast
   rpf-lookup-mode MODE``. ADDR specifies the multicast source address to look
   up.

   ::

      > show ip rpf 192.0.2.1
      Routing entry for 192.0.2.0/24 using Unicast RIB

      Known via "kernel", distance 0, metric 0, best
      * 198.51.100.1, via eth0


   Indicates that a multicast source lookup for 192.0.2.1 would use an
   Unicast RIB entry for 192.0.2.0/24 with a gateway of 198.51.100.1.

.. clicmd:: show ip rpf

   Prints the entire Multicast RIB. Note that this is independent of the
   configured RPF lookup mode, the Multicast RIB may be printed yet not
   used at all.

.. clicmd:: ip mroute PREFIX NEXTHOP [DISTANCE]


   Adds a static route entry to the Multicast RIB. This performs exactly as the
   ``ip route`` command, except that it inserts the route in the Multicast RIB
   instead of the Unicast RIB.

zebra Route Filtering

Zebra supports :dfn:`prefix-list` s and :ref:`route-map` s to match routes received from other FRR components. The permit/deny facilities provided by these commands can be used to filter which routes zebra will install in the kernel.

.. clicmd:: ip protocol PROTOCOL route-map ROUTEMAP

   Apply a route-map filter to routes for the specified protocol. PROTOCOL can
   be:

   - any,
   - babel,
   - bgp,
   - connected,
   - eigrp,
   - isis,
   - kernel,
   - nhrp,
   - openfabric,
   - ospf,
   - ospf6,
   - rip,
   - sharp,
   - static,
   - ripng,
   - table,
   - vnc.

   If you choose any as the option that will cause all protocols that are sending
   routes to zebra.  You can specify a :dfn:`ip protocol PROTOCOL route-map ROUTEMAP`
   on a per vrf basis, by entering this command under vrf mode for the vrf you
   want to apply the route-map against.

.. clicmd:: set src ADDRESS

   Within a route-map, set the preferred source address for matching routes
   when installing in the kernel.


The following creates a prefix-list that matches all addresses, a route-map that sets the preferred source address, and applies the route-map to all rip routes.

ip prefix-list ANY permit 0.0.0.0/0 le 32
route-map RM1 permit 10
     match ip address prefix-list ANY
     set src 10.0.0.1

ip protocol rip route-map RM1

IPv6 example for OSPFv3.

ipv6 prefix-list ANY seq 10 permit any
route-map RM6 permit 10
    match ipv6 address prefix-list ANY
    set src 2001:db8:425:1000::3

ipv6 protocol ospf6 route-map RM6

Note

For both IPv4 and IPv6, the IP address has to exist at the point the route-map is created. Be wary of race conditions if the interface is not created at startup. On Debian, FRR might start before ifupdown completes. Consider a reboot test.

.. clicmd:: zebra route-map delay-timer (0-600)

   Set the delay before any route-maps are processed in zebra.  The
   default time for this is 5 seconds.

zebra FIB push interface

Zebra supports a 'FIB push' interface that allows an external component to learn the forwarding information computed by the FRR routing suite. This is a loadable module that needs to be enabled at startup as described in :ref:`loadable-module-support`.

In FRR, the Routing Information Base (RIB) resides inside zebra. Routing protocols communicate their best routes to zebra, and zebra computes the best route across protocols for each prefix. This latter information makes up the Forwarding Information Base (FIB). Zebra feeds the FIB to the kernel, which allows the IP stack in the kernel to forward packets according to the routes computed by FRR. The kernel FIB is updated in an OS-specific way. For example, the Netlink interface is used on Linux, and route sockets are used on FreeBSD.

The FIB push interface aims to provide a cross-platform mechanism to support scenarios where the router has a forwarding path that is distinct from the kernel, commonly a hardware-based fast path. In these cases, the FIB needs to be maintained reliably in the fast path as well. We refer to the component that programs the forwarding plane (directly or indirectly) as the Forwarding Plane Manager or FPM.

.. program:: configure

The relevant zebra code kicks in when zebra is configured with the :option:`--enable-fpm` flag and started with the module (-M fpm or -M dplane_fpm_nl).

Note

The fpm implementation attempts to connect to 127.0.0.1 port 2620 by default without configurations. The dplane_fpm_nl only attempts to connect to a server if configured.

Zebra periodically attempts to connect to the well-known FPM port (2620). Once the connection is up, zebra starts sending messages containing routes over the socket to the FPM. Zebra sends a complete copy of the forwarding table to the FPM, including routes that it may have picked up from the kernel. The existing interaction of zebra with the kernel remains unchanged -- that is, the kernel continues to receive FIB updates as before.

The default FPM message format is netlink, however it can be controlled with the module load-time option. The modules accept the following options:

  • fpm: netlink and protobuf.
  • dplane_fpm_nl: none, it only implements netlink.

The zebra FPM interface uses replace semantics. That is, if a 'route add' message for a prefix is followed by another 'route add' message, the information in the second message is complete by itself, and replaces the information sent in the first message.

If the connection to the FPM goes down for some reason, zebra sends the FPM a complete copy of the forwarding table(s) when it reconnects.

For more details on the implementation, please read the developer's manual FPM section.

FPM Commands

fpm implementation

.. clicmd:: fpm connection ip A.B.C.D port (1-65535)

   Configure ``zebra`` to connect to a different FPM server than the default of
   ``127.0.0.1:2060``

.. clicmd:: show zebra fpm stats

   Shows the FPM statistics.

   Sample output:

   ::

       Counter                                       Total     Last 10 secs

       connect_calls                                     3                2
       connect_no_sock                                   0                0
       read_cb_calls                                     2                2
       write_cb_calls                                    2                0
       write_calls                                       1                0
       partial_writes                                    0                0
       max_writes_hit                                    0                0
       t_write_yields                                    0                0
       nop_deletes_skipped                               6                0
       route_adds                                        5                0
       route_dels                                        0                0
       updates_triggered                                11                0
       redundant_triggers                                0                0
       dests_del_after_update                            0                0
       t_conn_down_starts                                0                0
       t_conn_down_dests_processed                       0                0
       t_conn_down_yields                                0                0
       t_conn_down_finishes                              0                0
       t_conn_up_starts                                  1                0
       t_conn_up_dests_processed                        11                0
       t_conn_up_yields                                  0                0
       t_conn_up_aborts                                  0                0
       t_conn_up_finishes                                1                0


.. clicmd:: clear zebra fpm stats

   Reset statistics related to the zebra code that interacts with the
   optional Forwarding Plane Manager (FPM) component.


dplane_fpm_nl implementation

.. clicmd:: fpm address <A.B.C.D|X:X::X:X> [port (1-65535)]

   Configures the FPM server address. Once configured ``zebra`` will attempt
   to connect to it immediately.

   The ``no`` form disables FPM entirely. ``zebra`` will close any current
   connections and will not attempt to connect to it anymore.

.. clicmd:: fpm use-next-hop-groups

   Use the new netlink messages ``RTM_NEWNEXTHOP`` / ``RTM_DELNEXTHOP`` to
   group repeated route next hop information.

   The ``no`` form uses the old known FPM behavior of including next hop
   information in the route (e.g. ``RTM_NEWROUTE``) messages.

.. clicmd:: show fpm counters [json]

   Show the FPM statistics (plain text or JSON formatted).

   Sample output:

   ::

                        FPM counters
                        ============
                       Input bytes: 0
                      Output bytes: 308
        Output buffer current size: 0
           Output buffer peak size: 308
                 Connection closes: 0
                 Connection errors: 0
        Data plane items processed: 0
         Data plane items enqueued: 0
       Data plane items queue peak: 0
                  Buffer full hits: 0
           User FPM configurations: 1
         User FPM disable requests: 0


.. clicmd:: clear fpm counters

   Reset statistics related to the zebra code that interacts with the
   optional Forwarding Plane Manager (FPM) component.


Dataplane Commands

The zebra dataplane subsystem provides a framework for FIB programming. Zebra uses the dataplane to program the local kernel as it makes changes to objects such as IP routes, MPLS LSPs, and interface IP addresses. The dataplane runs in its own pthread, in order to off-load work from the main zebra pthread.

.. clicmd:: show zebra dplane [detailed]

   Display statistics about the updates and events passing through the
   dataplane subsystem.


.. clicmd:: show zebra dplane providers

   Display information about the running dataplane plugins that are
   providing updates to a FIB. By default, the local kernel plugin is
   present.


.. clicmd:: zebra dplane limit [NUMBER]

   Configure the limit on the number of pending updates that are
   waiting to be processed by the dataplane pthread.


zebra Terminal Mode Commands

.. clicmd:: show ip route

   Display current routes which zebra holds in its database.

Router# show ip route
Codes: K - kernel route, C - connected, S - static, R - RIP,
 B - BGP * - FIB route.

K* 0.0.0.0/0        203.181.89.241
S  0.0.0.0/0        203.181.89.1
C* 127.0.0.0/8      lo
C* 203.181.89.240/28      eth0
.. clicmd:: show ipv6 route

.. clicmd:: show [ip|ipv6] route [PREFIX] [nexthop-group]

   Display detailed information about a route. If [nexthop-group] is
   included, it will display the nexthop group ID the route is using as well.

.. clicmd:: show interface [NAME] [{vrf VRF|brief}] [nexthop-group]

.. clicmd:: show interface [NAME] [{vrf all|brief}] [nexthop-group]

   Display interface information. If no extra information is added, it will
   dump information on all interfaces. If [NAME] is specified, it will display
   detailed information about that single interface. If [nexthop-group] is
   specified, it will display nexthop groups pointing out that interface.

.. clicmd:: show ip prefix-list [NAME]

.. clicmd:: show route-map [NAME]

.. clicmd:: show ip protocol

.. clicmd:: show ip forward

   Display whether the host's IP forwarding function is enabled or not.
   Almost any UNIX kernel can be configured with IP forwarding disabled.
   If so, the box can't work as a router.

.. clicmd:: show ipv6 forward

   Display whether the host's IP v6 forwarding is enabled or not.

.. clicmd:: show zebra

   Display various statistics related to the installation and deletion
   of routes, neighbor updates, and LSP's into the kernel.

.. clicmd:: show zebra client [summary]

   Display statistics about clients that are connected to zebra.  This is
   useful for debugging and seeing how much data is being passed between
   zebra and it's clients.  If the summary form of the command is choosen
   a table is displayed with shortened information.

.. clicmd:: show zebra router table summary

   Display summarized data about tables created, their afi/safi/tableid
   and how many routes each table contains.  Please note this is the
   total number of route nodes in the table.  Which will be higher than
   the actual number of routes that are held.

.. clicmd:: show nexthop-group rib [ID] [vrf NAME] [singleton [ip|ip6]] [type]

   Display nexthop groups created by zebra.  The [vrf NAME] option
   is only meaningful if you have started zebra with the --vrfwnetns
   option as that nexthop groups are per namespace in linux.
   If you specify singleton you would like to see the singleton
   nexthop groups that do have an afi. [type] allows you to filter those
   only coming from a specific NHG type (protocol).


Router-id

Many routing protocols require a router-id to be configured. To have a consistent router-id across all daemons, the following commands are available to configure and display the router-id:

.. clicmd:: [ip] router-id A.B.C.D

   Allow entering of the router-id.  This command also works under the
   vrf subnode, to allow router-id's per vrf.

.. clicmd:: [ip] router-id A.B.C.D vrf NAME

   Configure the router-id of this router from the configure NODE.
   A show run of this command will display the router-id command
   under the vrf sub node.  This command is deprecated and will
   be removed at some point in time in the future.

.. clicmd:: show [ip] router-id [vrf NAME]

   Display the user configured router-id.

For protocols requiring an IPv6 router-id, the following commands are available:

.. clicmd:: ipv6 router-id X:X::X:X

   Configure the IPv6 router-id of this router. Like its IPv4 counterpart,
   this command works under the vrf subnode, to allow router-id's per vrf.

.. clicmd:: show ipv6 router-id [vrf NAME]

   Display the user configured IPv6 router-id.


Debugging

.. clicmd:: debug zebra mpls [detailed]

   MPLS-related events and information.

.. clicmd:: debug zebra events

   Zebra events

.. clicmd:: debug zebra nht [detailed]

   Nexthop-tracking / reachability information

.. clicmd:: debug zebra vxlan

   VxLAN (EVPN) events

.. clicmd:: debug zebra pseudowires

   Pseudowire events.

.. clicmd:: debug zebra packet [<recv|send>] [detail]

   ZAPI message and packet details

.. clicmd:: debug zebra kernel

   Kernel / OS events.

.. clicmd:: debug zebra kernel msgdump [<recv|send>]

   Raw OS (netlink) message details.

.. clicmd:: debug zebra rib [detailed]

   RIB events.

.. clicmd:: debug zebra fpm

   FPM (forwarding-plane manager) events.

.. clicmd:: debug zebra dplane [detailed]

   Dataplane / FIB events.

.. clicmd:: debug zebra pbr

   PBR (policy-based routing) events.

.. clicmd:: debug zebra mlag

   MLAG events.

.. clicmd:: debug zebra evpn mh <es|mac|neigh|nh>

   EVPN multi-hop events.

.. clicmd:: debug zebra nexthop [detail]

   Nexthop and nexthop-group events.