How to Identify Mutual Access Between Local VPNs?

Mutual access between local VPNs is implemented by configuring VPN targets of VPN instances. If VPN targets of VPN instances are advertised and imported mutually, mutual access between local VPNs is implemented.

For example:

#
ip vpn-instance vpna
 ipv4-family
  route-distinguisher 1000:1
  vpn-target 1000:0 200:0 export-extcommunity
  vpn-target 1000:0 200:0 import-extcommunity
#
ip vpn-instance vpnb
 ipv4-family
  route-distinguisher 200:2
  vpn-target 200:0 1000:0 export-extcommunity
  vpn-target 200:0 1000:0 import-extcommunity