Abstract: A storage router and related method are presented for combining multiple host frames, such as Fiber Channel frames, together into a single datagram for tunneling transmission over an IP or similar network. The storage router operates by storing incoming host frames in a host frame buffer. When there is sufficient data in the buffer, multiple host frames are batched together, compressed, and converted into an IP datagram. The number of host frames to be batched together can be established through a variety of tests, including total bytes of data, number of frames, or through a time-out mechanism. The network layer then fragments the datagram into data link level frames, such as 1500 byte Ethernet frames. When the datagram arrives at the final destination, the segmented datagram is reconstructed, decompressed, and the multiple host frames are then extracted and passed on to the recipient host frame network.

Abstract: A storage area network (SAN) fabric stores configuration information for servers connected to the SAN fabric. Configuration data can include target boot device address, topology configuration, etc. The configuration data is stored in a zone database as a zone member list. The zone database is accessible via a name server. To boot from a target boot device connected to the SAN fabric, the server first logs in to the fabric to register with the name server. The server then sends a configuration query to the name server. The name server replies with a member list that includes the address of the target boot device. The server establishes communication with the target boot device and accesses the boot code. The server then runs the boot code to initiate the boot process.

Abstract: Stateful failover redundancy support is provided for network address translation (NAT). A master NAT device is backed-up with at least one back-up NAT device. Existing sessions are synchronized between the two NAT devices, such as via a dedicated link between them. In the event of a failover where the master NAT device is unable to perform its NAT functions, ownership of Internet protocol (IP) addresses is transferred from the master NAT device to the back-up NAT device. The back-up NAT device, which is now owner of the IP addresses, assumes the NAT functionality associated with these IP addresses and continues the existing sessions, as well as processing new sessions.

Abstract: A method of routing traffic in a switch includes forming an optimized routing table specifying for each switch ingress port an exit port to be utilized to reach a specified destination domain. The optimized routing table is formed in accordance with load distribution, oversubscription, and fragmentation criteria. The optimized routing table is distributed to a set of ingress ports of the switch. Traffic is processed at the set of ingress ports in accordance with the optimized routing table.

Abstract: A diagnostic testing utility is used to perform single link diagnostics tests including an electrical loopback test, an optical loopback test, a link traffic test, and a link distance measurement test. To perform the diagnostic tests, two ports at each end of a link are identified and then statically configured by a user. The ports will be configured as D_Ports and as such will be isolated from the fabric with no data traffic flowing through them. The ports will then be used to send test frames to perform the diagnostic tests.

Abstract: A solution for network packet latency measurement includes, at a network device having a memory, storing a first time value indicating when an ingress port of the network device received a packet. The solution also includes storing a second time value indicating when an egress port of the network device received the packet for transmission towards another network device. The solution also includes storing a difference between the first time value and the second time value.

Abstract: Manageability tools are provided for allowing an administrator to have better control over switches in a lossless network of switches. These tools provide the ability to detect slow drain and congestion bottlenecks, detect stuck virtual channels and loss of credits, configure hold times on edge switches to be different from hold times on core switches, and mitigate severe latency bottlenecks.

Abstract: Techniques for optimizing traffic flows via dynamic routing protocol (DRP) modifications when server virtualization is used with dynamic routing are provided. In one embodiment, a network device can determine that it is part of a system of network devices acting as a virtual router. The network device can then transmit, to a client device, a DRP control packet that includes an interface IP address of the network device and a virtual IP address of the virtual router. In a further embodiment, the client device can receive the DRP control packet and store the interface IP address and the virtual IP address in a routing database. At the time of computing routing entries based on the routing database (via., e.g., a shortest path first (SPF) algorithm), the client device can replace, in entries that identify the interface IP address as the next hop, the interface IP address with the virtual IP address.

Abstract: Techniques for optimizing traffic flows via MAC synchronization when server virtualization is used with dynamic routing are provided. In one embodiment, a first network device can store an interface MAC address of a second network device in an L2 forwarding table, where the first network device and the second network device are peer nodes in an MC-LAG cluster. Further, the first network device can enable a flag for the interface MAC address in the L2 forwarding table. When the first network device receives a data packet that includes the interface MAC address of the second network device as a destination MAC address, the first network device can determine that the interface MAC address is included in the L2 forwarding table with the flag enabled. The first network device can then perform a lookup into its L3 routing table, identify a next hop destination for the data packet, and route the packet to the destination.

Abstract: File system disaster recovery techniques provide automated monitoring, failure detection and multi-step failover from a primary designated target to one of a designated group of secondary designated targets. Secondary designated targets may be prioritized so that failover occurs in a prescribed sequence. Replication of information between the primary designated target and the secondary designated targets allows failover in a manner that maximizes continuity of operation. In addition, user-specified actions may be initiated on failure detection and/or on failover operations and/or on failback operations.

Abstract: A system includes a source storage device, a target storage device, a host coupled to the source storage device and the target storage device, and a first migration device coupled to the source storage device and the target storage device. The first migration device includes a first virtual storage device. The first migration device is configured to migrate data from the source storage device to the target storage device, and the first virtual storage device is configured to receive write access requests for the data from the host during the data migration and send the access request to the source storage device and target storage device.

Abstract: One embodiment of the present invention provides a switch. The switch comprises one or more ports, a link management module and a load balancing module. The link management module operates a port of the one or more ports of the switch in conjunction with a remote switch to form a virtual link aggregation. The load balancing module generates an index of a weight distribution vector based on address information of a multicast group associated with the virtual link aggregation. A slot of the weight distribution vector corresponds to a respective switch participating in the virtual link aggregation. In response to the index indicating a slot corresponding to the switch, the load balancing module designates the switch as primary switch for the multicast group, which is responsible for forwarding multicast data of the multicast group via the virtual link aggregation.

Abstract: A chassis-based processing system includes a first set of processing blades mounted in parallel within a card cage and attached to a backplane within a chassis. An air intake plenum allows air to flow into the chassis, and over the first set of processing blades in an optimized manner. A separate processing blade is located in the air intake plenum, and is attached to the backplane. This processing blade may have less restrictive proximity requirements than the first set of processing blades. The processing blade in the plenum is positioned perpendicular to the first set of processing blades. As a result, airflow over the processing blade in the plenum has a different orientation than airflow over the first set of processing blades. An air deflector structure in the plenum deflects some of the air flowing into the plenum onto the processing blade located in the plenum, thereby providing improved cooling.

Abstract: A network switch allows defining a virtual port worldwide name (VPWWN) and associating the VPWWN with an F_port of the network switch, for use by a host bus adaptor (HBA) connecting to the network switch. Both a default and a user VPWWN may be defined, with the user VPWWN typically taking precedence over the default VPWWN. A database of VPWWN associations may be used to ensure uniqueness of the user VPWWN. Where the HBA allows dynamic assignment of WWNs, the VPWWN may be pushed to the HBA. The VPWWNs may be deleted, and moved to another port as desired.

Abstract: Manageability tools are provided for allowing an administrator to have better control over switches in a lossless network of switches. These tools provide the ability to detect slow drain and congestion bottlenecks, detect stuck virtual channels and loss of credits, while hold times on edge ASICs to be different from hold times encore ASICs, and mitigate severe latency bottlenecks.

Abstract: Techniques for synchronizing data object instances between applications/processes in an efficient manner. In one set of embodiments, the techniques described herein can be implemented in one or more network routers to synchronize data between a process running on an active management processor and a process running on a standby management processor, thereby facilitating features such as non-stop routing (NSR).

Abstract: Techniques for assigning device identifiers in a system of devices are provided. In one embodiment, a master device of the system can maintain a first configuration that specifies a set of links between a first subset of the devices, where the first configuration includes a device identifier for each device in the first subset. The master device can further generate a second configuration that specifies a set of links between a second subset of the devices, where the second configuration is based on a physical topology of the system, and where one or more devices in the second subset are unknown devices that are not associated with a device identifier in the physical topology. The master device can then assign device identifiers to the unknown devices in the second subset by comparing the first configuration with the second configuration.

Abstract: A SAN management software program controls access to resources in the SAN by associating individual users with one or more administration domains. A user that is associated with an administration domain that includes a port of a SAN switch can configure or otherwise access the port but is restricted from accessing ports outside of that administration domain. Likewise, access to other sub-fabric resources can be restricted and allowed to individual users and users in specific roles or groups. In this manner, the SAN administrative user has very specific control over which users can access which SAN resources and what level of access these users are granted.

Abstract: Stateful failover redundancy support is provided for network address translation (NAT). A master NAT device is backed-up with at least one back-up NAT device. Existing sessions are synchronized between the two NAT devices, such as via a dedicated link between them. In the event of a failover where the master NAT device is unable to perform its NAT functions, ownership of Internet protocol (IP) addresses is transferred from the master NAT device to the back-up NAT device. The back-up NAT device, which is now owner of the IP addresses, assumes the NAT functionality associated with these IP addresses and continues the existing sessions, as well as processing new sessions.

Abstract: A smoothing algorithm for round trip time (RTT) measurements is provided to a network device to effectively deal with variations or other potential anomalies that may occur in RTT measurements. The algorithm involves: first determining what should be considered a very high or a very small value for a RTT sample. If a new RTT sample is in an acceptable range, then the network device performs a relatively basic smoothing. If the new RTT sample is much higher than a current RTT value, then the network device ignores the value of this RTT sample a few times. If the network device still detects this large value after ignoring that value for some time, then the network device factors this value into the current RTT value using an additive increase. Similarly, if the value of the new RTT sample is much lower than current RTT value, the network device ignores the value of the new RTT sample a few times.