Loopback firewall filter scale optimization

You can increase the number of ingress firewall filters on the loopback interface from 384 to 768. To do this, you configure an ingress firewall filter, apply it to the loopback interface, and then use the loopback-firewall-optimization command at the [edit chassis hierarchy level] to enable optimization. When you configure the loopback filter, you must explicitly specify the terms for reserved multicast destination and ttl exception packets for this feature to work properly. Enabling or disabling optimization causes the PFE process to restart. This flaps the interfaces, meaning they go up and down, so traffic drops are expected.