doc: add neighbor PEER dont-capability-negotiate hostname command

improve bgp doc

Signed-off-by: Francois Dumontet <[email protected]>

doc/user/bgp.rst

@@ -2118,7 +2118,6 @@ Capability Negotiation
 
 .. clicmd:: neighbor PEER strict-capability-match
 
-
    Strictly compares remote capabilities and local capabilities. If
    capabilities are different, send Unsupported Capability error then reset
    connection.
@@ -2148,6 +2147,16 @@ Capability Negotiation
    hostname support, AS4, Addpath, Route Refresh, ORF, Dynamic Capabilities,
    and graceful restart.
 
+.. clicmd:: neighbor PEER dont-capability-negotiate hostname
+
+   Suppress sending hostname Capability in Negotiation as OPEN message
+   optional parameter to the peer. This command only affects the peer.
+
+   When remote peer does not support nor hostname capability feature and
+   nor capability negotiation feature, remote peer will not respond to the
+   OPEN with hostname capability. In that case, bgp tries to configures
+   the peer without the hostname capability.
+
 .. clicmd:: neighbor PEER override-capability
 
    Override the result of Capability Negotiation with local configuration.