Near-hitless upgrade or fast bootup with virtualized hardware

1. A network device comprising:

a host processor executing instructions for control-plane operations that manage and maintain a plurality of data-plane-associated tables of a switch-fabric of the network device;

a network interface;

a memory having computer readable instructions, wherein execution of the computer readable instruction, cause the host processor to:

establish, via the network interface, a network connection with a remote computing device comprising a remote processor;

direct the remote computing device to instantiate a virtualized standby switch, wherein the instantiated virtualized standby switch is configured to execute a set of instructions to manage and maintain the plurality of data-plane-associated tables of the switch-fabric of the network device;

synchronize control-plane states of the virtualized standby switch with control-plane states of the network device; and

reset the host processor to boot-up with a new system image in an upgrade or boot-up process, wherein during the upgrade process, the virtualized standby switch is configured to update, via data-plane transaction messages over the network interface, one or more of the plurality of data-plane-associated tables, and states of the network device, wherein the virtualized standby switch provides near-hitless operation of the network switch while the host processor is unavailable during the upgrade or boot-up process.

2. The network device of claim 1 , further comprising:

a second processor unit or upgrade logic circuit configured to:

write a first set of bus-interconnect transactions to a bus-interconnect of the network device based on a first set of data-plane transaction messages received from the virtualized standby switch over the network interface, wherein the first set of bus-interconnect transactions updates a portion of the plurality of data-plane-associated tables of the network device; and

read a second set of bus-interconnect transactions from the bus interconnect and transmit the second set of bus-interconnect transactions as a second set of data-plane transaction messages to the virtualized standby switch over the network interface, wherein the virtualized standby switch is configured to write a second set of bus-interconnect transactions to the bus interconnect or to a host processor of the virtualized standby switch based on the second set of data-plane transaction messages to update control plane states maintained by the virtualized standby switch.

3. The network device of claim 1 , wherein the computer readable instruction, when executed by the host processor, cause the host processor to establish a tunnel connection or a direct connection with the virtualized standby switch.

4. The network device of claim 1 , wherein the computer readable instructions to synchronize the control-plane states of the virtualized standby switch with the control-plane states of the network device comprises instructions for switchover operations with a physical switch.

5. The network device of claim 1 , wherein the control-plane associated message comprises protocol state machine updates.

6. The network device of claim 1 , wherein the network device comprises a non-redundant stackable switch.

7. The network device of claim 2 , wherein the network interface and the second processor unit or upgrade logic circuit is a part of a plug-able module that is connected to a bus-interconnect of the network device.

8. The network device of claim 1 wherein the synchronization operation is performed using at least one of high availability (HA) operations, In-Service Software Upgrade (ISSU) operations, and Stateful Switchover (SSO) operations.

9. The network device of claim 1 , wherein the virtualized standby switch is configured to synchronize with the control-plane states of the network device over a finite period.

10. The network device of claim 1 , wherein the network device directs the remote computing device to instantiate the virtualized standby switch by directing the remote computing device to retrieve a system image of the network device from an image server.

11. The network device of claim 1 , wherein the update of the one or more of the plurality of data-plane-associated tables and states of the network device includes at least one of:

updates associated with newly learnt MAC entries;

updates associated with Layer 3 entries;

updates associated with EtherChannel membership;

updates associated with Spanning Tree Protocol topology-change;

updates associated with protocol state or resource state change; and

updates associated with hardware resource transition change.

12. The network device of claim 1 , wherein the network connection comprises a front-side interchassis system link of the switch.

13. The network device of claim 1 , wherein the network connection comprises a back-side interchassis system link of the switch that connects to a communication link across an adapter.

14. The network device of claim 1 , wherein the computer readable instructions includes instructions to synchronize the control-plane states of the network device with the control-plane states of the virtualized standby switch after the host processor boot-ups with the new system image.

15. A method to upgrade a non-redundant stackable switch comprising a host processor executing a system image, the method comprising:

establishing, via a network interface of the stackable switch, a network connection with a remote computing device comprising a remote processor;

directing the remote computing device to instantiate a virtualized standby switch, wherein the instantiated virtualized standby switch is configured to execute a set of instructions to manage and maintain the plurality of data-plane-associated tables of the switch-fabric of the network device;

synchronizing, over a switchover operation, control-plane states of the virtualized standby switch with control-plane states of the network device; and

resetting the host processor to boot-up with a new system image in an upgrade or boot-up process, wherein during the upgrade process, the virtualized standby switch is configured to update, via data-plane transaction messages over the network interface, one or more of the plurality of data-plane-associated tables, and states of the network device, wherein the virtualized standby switch provides near-hitless operation of the network switch while the host processor is unavailable during the upgrade or boot-up process.

16. The method of claim 15 , further comprising:

receiving, over the network interface, a first set of data-plane transaction messages from the virtualized standby switch;

writing a first set of bus-interconnect transactions to a bus-interconnect of the stackable switch based on the received first set of data-plane transaction messages, wherein the first set of bus-interconnect transactions updates a portion of the plurality of data-plane-associated tables of the network device;

reading, from the bus interconnect, a second set of bus-interconnect transactions from the data-plane of the stackable switch; and

transmitting, to the virtualized standby switch, over the network interface, a second set of data-plane transaction messages generated based on the second set of bus-interconnect transactions, wherein the virtualized standby switch is configured to write a second set of bus-interconnect transactions to the bus interconnect of the virtualized standby switch based on the second set of data-plane transaction messages to update control plane states maintained by the virtualized standby switch.

17. The method of claim 15 , wherein the update of the one or more of the plurality of data-plane-associated tables and states of the network device includes at least one of:

updates associated with newly learnt MAC entries;

updates associated with Layer 3 entries;

updates associated with EtherChannel membership;

updates associated with Spanning Tree Protocol topology-change;

updates associated with protocol state or resource state change; and

updates associated with hardware resource transition change.

18. A non-transitory computer readable medium comprising computer readable instructions, wherein execution of the computer readable instruction by a processor of a network device, cause the processor to:

establish, via a network interface of the network device, a network connection with a remote computing device comprising a remote processor;

direct the remote computing device to instantiate a virtualized standby switch, wherein the instantiated virtualized standby switch is configured to execute a set of instructions to manage and maintain the plurality of data-plane-associated tables of the switch-fabric of the network device;

synchronize control-plane states of the virtualized standby switch with control-plane states of the network device; and

reset the host processor to boot-up with a new system image in an upgrade or boot-up process, wherein during the upgrade process, the virtualized standby switch is configured to update, via data-plane transaction messages over the network interface, one or more of the plurality of data-plane-associated tables, and states of the network device, wherein the virtualized standby switch provides near-hitless operation of the network switch while the host processor is unavailable during the upgrade or boot-up process.

19. The non-transitory computer readable medium of claim 18 , wherein the computer readable instructions, when executed by the processor, further cause the processor to:

receive, over the network interface, a first set of data-plane transaction messages from the virtualized standby switch;

write a first set of bus-interconnect transactions to a bus-interconnect of a stackable switch based on the received first set of data-plane transaction messages, wherein the first set of bus-interconnect transactions updates a portion of the plurality of data-plane-associated tables of the network device;

read, from the bus interconnect, a second set of bus-interconnect transactions from the data plane; and

transmitting, to the virtualized standby switch, over the network interface, a second set of data-plane transaction messages generated based on the second set of bus-interconnect transactions, wherein the virtualized standby switch is configured to write a second set of bus-interconnect transactions to the bus interconnect or a host processor of the virtualized standby switch based on the second set of data-plane transaction messages to update control plane states maintained by the virtualized standby switch.