公开(公告)号：US20240031295A1

公开(公告)日：2024-01-25

申请号：US17870578

申请日：2022-07-21

Applicant: Cisco Technology, Inc.

Inventor： Harsha Bharadwaj ,  Ramesh Sivakolundu

IPC: H04L47/193 ,  G06F3/06 ,  H04L47/263

CPC classification number: H04L47/193 ,  G06F3/0613 ,  G06F3/0659 ,  G06F3/067 ,  H04L47/263

Abstract: A method of congestion mitigation may include determining whether a host is sending a read command or a write command to an NVMe controller, and in response to a determination that the host is sending the read command, transmitting the read command via a first transmission control protocol (TCP) connection between the host and the NVMe controller. The method may further include in response to a determination that the host is sending the write command, transmitting the write command via a second TCP connection between the host and the NVMe controller.

公开(公告)号：US11297006B1

公开(公告)日：2022-04-05

申请号：US16891321

申请日：2020-06-03

Applicant: Cisco Technology, Inc.

Inventor： Harsha Bharadwaj

IPC: H04L12/947 ,  H04L49/25 ,  H04L49/9005 ,  H04L49/00

Abstract: A method is performed at a switch fabric that communicates with a storage array target port. The method includes sending frames to the target port responsive to receiving buffer-to-buffer (B2B) credits that indicate a receive buffer at the target port is available for the frames. The method further includes, in response to detecting a credit stall at the target port, operating in a virtual lane mode. The operating in the virtual lane mode includes: determining whether a frame destined for the target port is a command frame or a data frame; based on the determining, marking the frame to indicate that the frame is destined for a particular virtual lane among virtual lanes of the receive buffer; and receiving from the target port a per-virtual lane B2B credit that indicates the particular virtual lane is available and, in responsive, sending the frame to that virtual lane on the target port.

公开(公告)号：US11252067B2

公开(公告)日：2022-02-15

申请号：US16280870

申请日：2019-02-20

Applicant: Cisco Technology, Inc.

Inventor： Harsha Bharadwaj ,  Nagendran Venugopalan

IPC: H04L12/26 ,  H04L29/08 ,  H04B10/077 ,  H04L1/24

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.

公开(公告)号：US10938702B2

公开(公告)日：2021-03-02

申请号：US16551336

申请日：2019-08-26

Applicant: Cisco Technology, Inc.

Inventor： Harsha Bharadwaj

IPC: H04L12/26 ,  H04L12/935 ,  H04L12/823

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.

公开(公告)号：US10394469B2

公开(公告)日：2019-08-27

申请号：US15670263

申请日：2017-08-07

Applicant: Cisco Technology, Inc.

Inventor： Harsha Bharadwaj ,  Edward D. Mazurek

IPC: G06F3/06 ,  G06F13/40 ,  G06F13/42 ,  G06F16/23 ,  G06N20/00

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.

公开(公告)号：US10389550B1

公开(公告)日：2019-08-20

申请号：US15949521

申请日：2018-04-10

Applicant: Cisco Technology, Inc.

Inventor： Harsha Bharadwaj

IPC: H04L12/40 ,  H04L12/751 ,  H04L29/08

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.

公开(公告)号：US20160088083A1

公开(公告)日：2016-03-24

申请号：US14492036

申请日：2014-09-21

Applicant: CISCO TECHNOLOGY, INC.

Inventor： Harsha Bharadwaj ,  Prabesh Babu Nanjundaiah

IPC: H04L29/08 ,  H04L12/26

CPC classification number: H04L67/1097 ,  H04L12/4625 ,  H04L41/0631 ,  H04L43/02 ,  H04L43/04 ,  H04L43/0847 ,  H04L43/0852 ,  H04L43/18

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 translation: 提供了一种用于存储区域网络（SAN）环境中的性能监视和故障排除的示例性方法，包括在SAN中的网络元件处接收SAN中的发起者和目标之间的交换的多个帧， 起始帧和多个帧中的交换的结束帧，将所述交换的开始帧和结束帧复制到所述网元中的网络处理器，由所述网络处理器提取相应的一部分字段的值 起始帧和结束帧的头部，并且由网络处理器基于该值计算归一化交换完成时间（ECT）。

公开(公告)号：US11909669B2

公开(公告)日：2024-02-20

申请号：US17705994

申请日：2022-03-28

Applicant: Cisco Technology, Inc.

Inventor： Harsha Bharadwaj ,  Santhosh Hanumana Gowda

IPC: H04L49/356 ,  G06F13/40 ,  H04L43/16 ,  H04L67/1097 ,  H04L67/1001

CPC classification number: H04L49/357 ,  G06F13/4022 ,  H04L43/16 ,  H04L67/1001 ,  H04L67/1097

Abstract: A method includes measuring input/output traffic for respective hosts that are connected to a Fibre Channel N_Port Virtualizer (FC-NPV) switch, which is in communication with a first N_Port ID Virtualization (NPIV) core switch via a first port channel and with a second NPIV core switch via a second port channel; determining that traffic carried on the first port channel between the FC-NPV switch and the first NPIV Core switch exceeds a predetermined threshold compared to traffic carried on the second port channel; and re-assigning traffic from a given host carried on the first port channel to the second port channel between the FC-NPV switch and the second NPIV core switch.

公开(公告)号：US20190386906A1

公开(公告)日：2019-12-19

申请号：US16551336

申请日：2019-08-26

Applicant: Cisco Technology, Inc.

Inventor： Harsha Bharadwaj

IPC: H04L12/26 ,  H04L12/823 ,  H04L12/935

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.

公开(公告)号：US20190324665A1

公开(公告)日：2019-10-24

申请号：US16456753

申请日：2019-06-28

Applicant: Cisco Technology, Inc.

Inventor： Harsha Bharadwaj ,  Edward D. Mazurek

IPC: G06F3/06 ,  G06F13/40 ,  G06N20/00 ,  G06F13/42 ,  G06F16/23

Abstract: A Fibre 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.