frr: T4020: document multiple per daemon config knobs

docs/configuration/system/frr.rst

@@ -0,0 +1,38 @@
+.. _system_frr:
+
+###
+FRR
+###
+
+VyOS uses [FRRouting](https://frrouting.org/) as the control plane for dynamic
+and static routing. The routing daemon behavior can be adjusted during runtime,
+but require either a restart of the routing daemon, or a reboot of the system.
+
+.. cfgcmd:: set system frr bmp
+
+   Enable :abbr:`BMP (BGP Monitoring Protocol)` support
+
+.. cfgcmd:: set system frr descriptors <numer>
+
+   This allows the operator to control the number of open file descriptors
+   each daemon is allowed to start with. If the operator plans to run bgp with
+   several thousands of peers then this is where we would modify FRR to allow
+   this to happen.
+
+.. cfgcmd:: set system frr irdp
+
+   Enable ICMP Router Discovery Protocol support
+
+.. cfgcmd:: set system frr snmp <daemon>
+
+   Enable SNMP support for an individual routing daemon.
+
+   Supported daemons:
+
+   - bgpd
+   - isisd
+   - ldpd
+   - ospf6d
+   - ospfd
+   - ripd
+   - zebra

docs/configuration/system/index.rst

@@ -11,6 +11,7 @@ System
    conntrack
    console
    flow-accounting
+   frr
    host-name
    ip
    ipv6