Handling CPU-Bound Packets in Multi-Chassis Systems During Hitless Reboot

A network device that is part of a multi-chassis system comprising a plurality of network devices, the network device comprising:

• a data plane;
• and
• a control plane including a central processing unit (CPU) and a main memory, the main memory having stored thereon program code that when executed by the CPU causes the CPU to, at a time of shutting down the control plane for a hitless reboot:
• identify one or more rules programmed in the data plane that:
• are configured on an ingress interface of a multi-chassis link aggregation group (MLAG) to which the network device is connected;
• and
• specify the CPU as a destination for matched network traffic;
• and
• for each of the identified rules, change the rule to specify an inter-chassis link between the network device and another network device in the plurality of network devices as the destination for matched network traffic.

A method performed by a peer in a plurality of peers comprising a multi-chassis system, the method comprising, at a time of shutting down a control plane of the peer:

• identifying one or more rules that:
• are configured on an interface of a multi-chassis link aggregation group (MLAG) which the peer is a part of;
• and
• specify a central processing unit (CPU) of the peer as a destination for matched network traffic;
• and
• for each of the identified rules, changing the rule to forward network traffic matching the rule to another peer in the plurality of peers rather than to the CPU.