Abstract: One embodiment is a method and includes periodically polling a plurality of interface counters associated with each of an edge port and an Inter-Switch Link (“ISL”) port of a first fiber channel (“FC”) switch, wherein a target device is connected to the edge port of the first FC switch, and a plurality of interface counters associated with ISL port of a second FC switch, wherein the ISL port of each of the first and second FC switches are connected to one another via an ISL; determining based on the polling of the various counters whether several conditions have been met for a predetermined number of times and if so, characterizing the edge port as a level 1 slow drain port and taking remedial action based on the characterization.

Abstract: A Fiber Channel (FC) or FC-over-Ethernet (FCoE) switch has ports to forward Input-Output (IO) requests, and service data transfers, between end devices in a storage area network. The switch receives at a port a time ordered sequence of IO requests for data transfers to be serviced by the port. Each IO request including a data length of the data transfer. The switch detects a microburst on the port for each IO request. To do this, the switch parses the IO request to retrieve the data length, determines a transfer time required to transfer the data length over the port, upon receiving a next IO request, determine whether a time interval between the IO request and the next IO request is less than the transfer time, and if the time interval is less than the transfer time, declaring a microburst on the port, otherwise not declaring a microburst.

Abstract: A host bus adapter of a target device is associated with a Fiber Channel driver and is connected to a Fiber Channel switch fabric. The host bus adapter receives from the switch fabric an inbound frame having a header including a source identifier and a virtual machine (VM) tag, stores a mapping between the source identifier and the VM tag, and passes the inbound frame to the Fiber Channel driver. The host bus adapter receives from the Fiber Channel driver an outbound frame having a header including a destination identifier, and determines, based on the mapping, whether there is a match at least between the source identifier of the inbound frame and the destination identifier of the outbound frame. If there is a match, the host bus adapter tags the header of the outbound frame with the VM tag, and transmits the tagged outbound frame to the switch fabric.

Abstract: A method is performed at a Fibre Channel (FC) switch of an FC switch fabric through which servers connected to the FC switch fabric access logical partitions of a storage array connected to the FC switch fabric. The FC switch receives from the storage array information indicative of port zoning rules and logical partition masking that collectively define which server ports are permitted access to which storage array ports and to which logical partitions of the storage array. The FC switch generates from the information authorization rules for enforcing the port zoning rules and the logical partition masking, and programs the authorization rules into memory. The FC switch receives FC frames from the server ports. The FC frames convey respective input-output (IO) operations destined for the logical partitions. The FC switch authorizes each IO operation based on a lookup of the programmed authorization.

Abstract: One embodiment is a method including configuring a first network element of a fibre channel (“FC”) network as a generator element, wherein the generator employs a link diagnostic protocol to cause a second network element comprising a peer of the first network element as a reflector element, wherein the first and second elements are connected via a link; entering a first diagnostic phase, wherein in the first diagnostic phase, diagnostic capabilities of the first and second elements are determined; and subsequent to completion of the first diagnostic phase, entering a second diagnostic phase in which a deep loopback test is performed, wherein the deep loopback test comprises a frame level loopback test for exposing an issue in a path between the first and second network elements beyond a Media Access Control (“MAC”) layer.

Abstract: A method is described and in one embodiment includes monitoring by an integrated circuit device READ/WRITE commands in connection with a flow of an application executing in a Fiber Channel Storage Area Network (“FC-SAN”); determining from the monitored READ/WRITE commands at least one metric for characterizing I/O performance of the application with respect to a storage device, wherein the at least one metric includes at least one of an inter I/O gap (“IIG”), a Logical Unit Number (“LUN”) I/O access pattern (“IAP”), relative block size, I/O operations per second (“IOPS”) and throughput, and IOPS per virtual server; storing the calculated at least one metric in a flow record associated with the flow; and using the calculated at least one metric to identify a storage device for use by the flow, wherein the calculated at least one metric is indicative of a performance of the application in the FC-SAN.

Abstract: One embodiment is a method including configuring a first network element of a fiber channel (“FC”) network as a generator element, wherein the generator employs a link diagnostic protocol to cause a second network element comprising a peer of the first network element as a reflector element, wherein the first and second elements are connected via a link; entering a first diagnostic phase, wherein in the first diagnostic phase, diagnostic capabilities of the first and second elements are determined; and subsequent to completion of the first diagnostic phase, entering a second diagnostic phase in which a deep loopback test is performed, wherein the deep loopback test comprises a frame level loopback test for exposing an issue in a path between the first and second network elements beyond a Media Access Control (“MAC”) layer.

Abstract: A Fibre Channel (FC) or FC-over-Ethernet (FCoE) switch has ports to forward Input-Output (TO) requests, and service data transfers, between end devices in a storage area network. The switch receives at a port a time ordered sequence of IO requests for data transfers to be serviced by the port. Each IO request including a data length of the data transfer. The switch detects a microburst on the port for each IO request. To do this, the switch parses the IO request to retrieve the data length, determines a transfer time required to transfer the data length over the port, upon receiving a next IO request, determine whether a time interval between the IO request and the next IO request is less than the transfer time, and if the time interval is less than the transfer time, declaring a microburst on the port, otherwise not declaring a microburst.

Abstract: A method is described and in one embodiment includes monitoring by an integrated circuit device READ/WRITE commands in connection with a flow of an application executing in a Fibre Channel Storage Area Network (“FC-SAN”); determining from the monitored READ/WRITE commands at least one metric for characterizing I/O performance of the application with respect to a storage device, wherein the at least one metric includes at least one of an inter I/O gap (“IIG”), a Logical Unit Number (“LUN”) I/O access pattern (“IAP”), relative block size, I/O operations per second (“IOPS”) and throughput, and IOPS per virtual server; storing the calculated at least one metric in a flow record associated with the flow; and using the calculated at least one metric to identify a storage device for use by the flow, wherein the calculated at least one metric is indicative of a performance of the application in the FC-SAN.

Abstract: One embodiment is a method and includes periodically polling a plurality of interface counters associated with each of an edge port and an Inter-Switch Link (“ISL”) port of a first fibre channel (“FC”) switch, wherein a target device is connected to the edge port of the first FC switch, and a plurality of interface counters associated with ISL port of a second FC switch, wherein the ISL port of each of the first and second FC switches are connected to one another via an ISL; determining based on the polling of the various counters whether several conditions have been met for a predetermined number of times and if so, characterizing the edge port as a level 1 slow drain port and taking remedial action based on the characterization.

Abstract: A method is provided in one example embodiment and includes monitoring an egress port connected to a server to detect a traffic flow comprising a plurality of data packets and determining whether one of the packets is timeout dropped at the egress port. If at least one of the packets is timeout dropped at the egress port, the method further includes detecting a destination identifier (“DID”) of the timeout dropped packet and withdrawing a device identified by the detected DID from an FC zone to which it is assigned and reactivating the zone. The method further includes determining whether the traffic flow is experiencing high wait times at the egress port and, if the traffic flow is experiencing high wait times at the egress port, detecting the DID of the traffic flow and reducing a priority of the zone to which the detected DID is assigned and reactivating the zone.

Abstract: In one example embodiment, a time unconstrained fabric switch software upgrade function is described for an in-switch-software-upgrade/downgrade (ISSU) in a network switch. Prior to an ISSU, Hello protocol data unit (PDU) information is stored for relevant control protocols of associated interfaces of the switch. The Hello PDU information comprises information on messages and data exchanged by the control protocols that may be used to maintain communications links of the switch. During the configuring of the ISSU, and while the control plane of the switch is, at least partially, dysfunctional, Hello PDUs are sent on the interfaces according to the stored PDU information in order to maintain the communication links. The Hello PDU information may include a time interval value for each relevant protocol that determines when Hello PDUs are sent.

Abstract: Techniques are provided for bifurcating database information that might otherwise be replicated on each switch in a switched fabric of a Storage Area Network (SAN). The database is divided into a control plane database that comprises mostly switch specific data and a central management database that comprises user device configurations and device profiles. The control plane database includes information such as name server and zone server information, for those devices that may locally log into the switched fabric via a given switch, and those remote devices that are zoned with those local devices and that may log into the switched fabric via another switch. The central management database includes global information for the switched fabric and device profile information (e.g., login interface, Virtual SAN membership, device aliasing, etc.) for devices that have access to the switched fabric and that can also be requested by the various switches in the switched fabric.

Abstract: A method is provided in one example embodiment and includes monitoring an egress port connected to a server to detect a traffic flow comprising a plurality of data packets and determining whether one of the packets is timeout dropped at the egress port. If at least one of the packets is timeout dropped at the egress port, the method further includes detecting a destination identifier (“DID”) of the timeout dropped packet and withdrawing a device identified by the detected DID from an FC zone to which it is assigned and reactivating the zone. The method further includes determining whether the traffic flow is experiencing high wait times at the egress port and, if the traffic flow is experiencing high wait times at the egress port, detecting the DID of the traffic flow and reducing a priority of the zone to which the detected DID is assigned and reactivating the zone.

Abstract: A method is provided in one example embodiment and includes monitoring an egress port connected to a server to detect a traffic flow comprising a plurality of data packets and determining whether one of the packets is timeout dropped at the egress port. If at least one of the packets is timeout dropped at the egress port, the method further includes detecting a destination identifier (“DID”) of the timeout dropped packet and withdrawing a device identified by the detected DID from an FC zone to which it is assigned and reactivating the zone. The method further includes determining whether the traffic flow is experiencing high wait times at the egress port and, if the traffic flow is experiencing high wait times at the egress port, detecting the DID of the traffic flow and reducing a priority of the zone to which the detected DID is assigned and reactivating the zone.

Abstract: Techniques are provided for bifurcating database information that might otherwise be replicated on each switch in a switched fabric of a Storage Area Network (SAN). The database is divided into a control plane database that comprises mostly switch specific data and a central management database that comprises user device configurations and device profiles. The control plane database includes information such as name server and zone server information, for those devices that may locally log into the switched fabric via a given switch, and those remote devices that are zoned with those local devices and that may log into the switched fabric via another switch. The central management database includes global information for the switched fabric and device profile information (e.g., login interface, Virtual SAN membership, device aliasing, etc.) for devices that have access to the switched fabric and that can also be requested by the various switches in the switched fabric.

Abstract: An example method for performance monitoring and troubleshooting in a storage area network (SAN) environment is provided and includes receiving, at a network element in the SAN, a plurality of frames of an exchange between an initiator and a target in the SAN, identifying a beginning frame and an ending frame of the exchange in the plurality of frames, copying the beginning frame and an ending frame of the exchange to a network processor in the network element, extracting, by the network processor, values of a portion of fields in respective headers of the beginning frame and the ending frame, and calculating, by the network processor, a normalized exchange completion time (ECT) based on the values.

Abstract: In one example embodiment, a time unconstrained fabric switch software upgrade function is described for an in-switch-software-upgrade/downgrade (ISSU) in a network switch. Prior to an ISSU, Hello protocol data unit (PDU) information is stored for relevant control protocols of associated interfaces of the switch. The Hello PDU information comprises information on messages and data exchanged by the control protocols that may be used to maintain communications links of the switch. During the configuring of the ISSU, and while the control plane of the switch is, at least partially, dysfunctional, Hello PDUs are sent on the interfaces according to the stored PDU information in order to maintain the communication links. The Hello PDU information may include a time interval value for each relevant protocol that determines when Hello PDUs are sent.

Abstract: In an example embodiment, a new qualifier is added to members in a Fiber Channel zone to specify whether each member is a target or initiator and in another embodiment a time-range attribute is added to a zone in the zoneset. When the zoneset is applied the number of ACL entries that must be programmed is reduced from k×(k?1) entries to 2(k?1) entries for a zone with k members where k?1 members are of one type (e.g. initiators) and one of the members is of a different type (e.g., a tape device). The time-range attribute is enforced by zone server software and enhances security by, for example, limiting access to sensitive data to specified times. In another embodiment, an incremental zoneset activation protocol is implemented where a hash of a zoneset is created by a switch updating the zoneset and the hash and ID of the switch updating the zoneset are sent to all other switches in the fabric when the zoneset is propagated. The hash and switch ID are stored in persistent storage at all switches in the fabric.

Abstract: In an example embodiment, a new qualifier is added to members in a Fibre Channel zone to specify whether each member is a target or initiator and in another embodiment a time-range attribute is added to a zone in the zoneset. When the zoneset is applied the number of ACL entries that must be programmed is reduced from k×(k?1) entries to 2(k?1) entries for a zone with k members where k?1 members are of one type (e.g. initiators) and one of the members is of a different type (e.g., a tape device). The time-range attribute is enforced by zone server software and enhances security by, for example, limiting access to sensitive data to specified times. In another embodiment, an incremental zoneset activation protocol is implemented where a hash of a zoneset is created by a switch updating the zoneset and the hash and ID of the switch updating the zoneset are sent to all other switches in the fabric when the zoneset is propagated. The hash and switch ID are stored in persistent storage at all switches in the fabric.