摘要:
A method and apparatus is disclosed for providing gateway anycast virtual MAC reachability in extended subnets. When an extended L2 subnet spans more than one geographical location, it is desirable that the gateway MAC addresses learned in each location be the same across all IP hosts. Accordingly, the gateway MAC address may be preserved (i.e., programmed) in more than one port on a bridge, such as both a local port and a LAN extension port. The bridge may forward traffic having the anycast MAC address to the closest instance of the MAC address, rather than replicating the traffic to the multiple ports on which the anycast MAC address is programmed. If the gateway reachable on the local port goes down, the frame may be forwarded to the local gateway in the second layer 2 subnet over the LAN extension port.
摘要:
A method and apparatus is disclosed for providing gateway anycast virtual MAC reachability in extended subnets. When an extended L2 subnet spans more than one geographical location, it is desirable that the gateway MAC addresses learned in each location be the same across all IP hosts. Accordingly, the gateway MAC address may be preserved (i.e., programmed) in more than one port on a bridge, such as both a local port and a LAN extension port. The bridge may forward traffic having the anycast MAC address to the closest instance of the MAC address, rather than replicating the traffic to the multiple ports on which the anycast MAC address is programmed. If the gateway reachable on the local port goes down, the frame may be forwarded to the local gateway in the second layer 2 subnet over the LAN extension port.
摘要:
In one embodiment, a method includes building an address resolution cache for a layer-3 router in a first layer-2 datacenter, where the address resolution cache includes a plurality of entries, each of the entries containing a host network address, a host hardware address, and a switch identifier for a switch serving a host, intercepting an address resolution flood within the first layer-2 datacenter that seeks address resolution for a host in a second layer-2 datacenter, and generating a response to the address resolution flood that indicates a source in the second layer-2 datacenter, where data indicating the source in the second layer-2 datacenter is accessed from the address resolution cache.
摘要:
An example method is provided and can include initiating a probe session at a source network element; identifying multiple paths from the source network element to a destination network element in a network; transmitting packets from the source network element along the multiple paths; compiling a list of network characteristics associated with the multiple paths; and selecting a particular one of the multiple paths for packet routing based on the network characteristics.
摘要:
A solution is provided wherein the interfaces between multiple chassis (e.g., edge switches) in a network of layer 2 devices and a spanning tree device are treated as a single emulated switch. This emulated switch effectively enables two different views to the two different sides. Thus, frames from the network of layer 2 switches destined to any port of the emulated switch may take any of the links (through any of the physical switches), thereby enabling effective load-balancing for frames traveling from the layer 2 network side into the spanning tree device. Meanwhile the spanning tree device does not recognize an illegal loop in its connection to two different edge switches as it views the two links as a single logical EtherChannel.
摘要:
An active-standby virtual port channel mechanism may be provided, where at any point only one virtual port channel link would be active. Upon failover of the active, a fast failover mechanism is employed to move active traffic to a standby port channel link.
摘要:
In one embodiment, an apparatus includes one or more ports for connection to one or more links in communication with a network device, a multi-chassis trunk (MCT) port for connection to an MCT in communication with a switch, and an MCEC manager for creating an MCEC comprising the one or more links in communication with the network device and one or more links connecting the switch to the network device, and transmitting messages to the switch to synchronize state for the MCEC. The apparatus further includes a control plane and a data plane configured for operation independent from a control plane and a data plane at the switch. A method is also disclosed.
摘要:
In one embodiment, a method includes configuring a first network device for operation in a first logical group with a second network device, receiving information from other network devices configured for operation in a second logical group, the information uniquely identifying each of the other network devices within the second logical group, and assigning a priority to each link connecting the first network device to the second logical group network devices. A portion of the links are selected as active links based on the link priorities and the link priorities are assigned such that a balance of active links is maintained across the second logical group network devices. An apparatus for maintaining a balance of active links across the network devices is also disclosed.
摘要:
In one embodiment, a method includes receiving a multi-destination packet at a switch in communication with a plurality of servers through a network device, identifying a port receiving the multi-destination packet at the switch or a forwarding topology for the multi-destination packet, selecting a bit value based on the identified port or forwarding topology, inserting the bit value into a field in a virtual network tag in the multi-destination packet, and forwarding the multi-destination packet with the virtual network tag to the network device. The network device is configured to forward the multi-destination packet to one or more of the servers based on the bit value in the multi-destination packet. An apparatus for forwarding multi-destination packets is also disclosed.
摘要:
In one embodiment, a first switch at a border between a first network of a first protocol (P1 network) and a first network of a second protocol (P2 network) is interconnected via the first P1 network with a second switch between a second P1 network (interconnected with the first P1 network) and a second P2 network. In response to detecting a merge of the first and second P2 networks, the first switch may: i) block data packets from traversing P1 network boundary ports of the first switch; ii) allow protocol messages to flow between the first and second P1 networks through the P1 network boundary ports of the first switch; iii) allow the first and second P1 networks to discover each other through the protocol messages and to prevent loops; and in response, iv) unblock the P1 network boundary ports of the first switch to allow traversal of data packets.