Because you use BGP to determine when a tunnel goes down,
consider the HoldTime value you have configured on your CPE. The
hold timer determines the amount of time that the tunnel is down
before removing the route.
Prisma Access
uses the default BGP HoldTime
value of 90 seconds as defined by RFC 4271. If you configure a lower
hold time for the BGP CPE in the remote network site, BGP uses the
lower hold time value. Palo Alto Networks recommends a KeepAlive
value of 10 seconds and a HoldTime value of 30 seconds for your
CPE with this deployment.