In a Virtual Route Reflector (VRR) setup, both the server and client are iBGP peers, meaning they share the same Autonomous System Number (ASN). Because of this, the client should not prepend its own AS to the AS path. If the client does prepend its AS, the server will reject the updates to prevent routing loops. As a result, these routes will not be added to the RIB-in (Routing Information Base inbound) and will be excluded from the routing table.

To ensure visibility of all advertised routes, including those with AS loops, the command set routing-options autonomous-system loops 3 can be used. This configuration allows the network administrator to see routes that may otherwise be hidden due to AS path issues, providing greater insight into the routing behavior within the VRR setup.

In a Virtual Route Reflector (VRR) setup, where the server and client are iBGP peers within the same Autonomous System Number (ASN), the client should not prepend its own AS to the AS path. If it does, the server will reject these updates to prevent routing loops, and these routes will not be added to the RIB-in (Routing Information Base inbound).

• Route Visibility: Routes that have been AS-looped will be dropped by the router before they reach the Routing Protocol Daemon (RPD). As a result, these routes will not appear under the show hidden route command.

AS-looped routes will be dropped even before coming to RPD by the router and will not be displayed under “show hidden route” command and can only be seen from bgp traceoptions, If “set protocol bgp keep all” is configured, these AS looped routes will be shown as hidden under "show route hidden" command https://www.juniper.net/documentation/us/en/software/junos/cli-reference/topics/ref/statement/keep-edit-protocols-bgp.html

Starting from 23.3 version, there is a command "show bgp diagnostics route" and "show bgp diagnostics dropped-route-cache" which will also show the dropped routes and dropped reason