Determining zoned but inactive I/O paths

Patent metadata

Field	Value
Publication number	US-11095547-B2
Application number	US-201916263042-A
Country	US
Kind code	B2
Filing date	Jan 31, 2019
Priority date	Jan 31, 2019
Publication date	Aug 17, 2021
Grant date	Aug 17, 2021

Abstract

Combinations of host ports and storage ports (e.g., I-T pairs) on a storage network that are zoned but not masked may be determined, without accessing a switch or network administrator. Heartbeat communications (heartbeats) may be transmitted from host systems to each storage device of a storage system of which the host system is aware, along the one or more I/O paths of which the host is aware to the storage port of the I/O path. The storage devices may include one or more nominal devices defined for I-T pairs for which I/O connectivity has not been defined for any storage devices. The storage system may maintain a master heartbeat (heartbeat) table that may include a plurality of entries, each entry corresponding to a combination of a host port, storage port and storage device, and storing a time stamp value for a most recent heartbeat received for the combination.

First claim

What is claimed is:

1. For a storage network including one or more host systems coupled to a storage system having a plurality of storage devices, a method comprising:
receiving a plurality of heartbeat communications at one or more storage ports of the storage system from the one or more host systems, each heartbeat communication indicative of current I/O connectivity between a combination of a respective host port of the one or more host systems and a respective one of the storage ports; and
determining from the heartbeat communications that, for each of one or more combinations of a host port and a storage port defining an I/O path: the combination has I/O connectivity currently enabled between the host port and the storage port on the I/O path, but no I/O connectivity currently enabled for any one of the plurality of storage devices over the I/O path defined between the host port and the storage port.

2. The method of claim 1 , further comprising:
maintaining a first data structure on the storage system, the first data structure including a plurality of entries, each entry corresponding to a combination of a storage port of the storage system and a host port of one of the one or more host systems between which I/O connectivity has been enabled at least at one point in time; and
in response to each heartbeat communication for each at least first combination, updating an entry of the first data structure that corresponds to the at least first combination with a time stamp value corresponding to a time at which the heartbeat communication was received at one of the storage ports,
wherein the determining includes determining from the first data structure that one or more combinations of a host port and a storage port have I/O connectivity currently enabled between the host port and storage device, but no I/O connectivity currently enabled between the host port and storage device for any of the plurality of storage devices.

3. The method of claim 2 , wherein maintaining the first data structure includes recording, for each combination of a host port and a storage port having an entry in the data structure, a time stamp value of a last heartbeat communication, if any, received for each combination.

4. The method of claim 2 , further comprising:
sorting two or more of the plurality of entries based at least in part on the time stamp values of the two or more entries.

5. The method of claim 2 , wherein each entry of the data structure was previously created when the host port corresponding to the entry logged into the storage port corresponding to the entry.

6. The method of claim 1 , further comprising:
one or more multi-path drivers of the one or more host systems sending the plurality of heartbeat communications.

7. The method of claim 1 , further comprising:
determining from the heartbeat communications that one or more combinations of a host port and a storage port do not have I/O connectivity currently enabled between the host port and storage device.

8. A storage system of a storage network including one or more host systems coupled to the storage system, the storage system comprising:
a plurality of storage devices;
one or more processors; and
a memory comprising code stored thereon that, when executed, performs a method comprising:
receiving a plurality of heartbeat communications at one or more storage ports of the storage system from the one or more host systems, each heartbeat communication indicative of current I/O connectivity between a combination of a respective host port of the one or more host systems and a respective one of the storage ports; and
determining from the heartbeat communications that, for each of one or more combinations of a host port and a storage port defining an I/O path: the combination has I/O connectivity currently enabled between the host port and the storage port on the I/O path, but no I/O connectivity currently enabled for any one of the plurality of storage devices over the I/O path defined between the host port and the storage port.

9. The system of claim 8 , the method further comprising:
maintaining a first data structure on the storage system, the first data structure including a plurality of entries, each entry corresponding to a combination of a storage port of the storage system and a host port of one of the one or more host systems between which I/O connectivity has been enabled at least at one point in time; and
in response to each heartbeat communication for each at least first combination, updating an entry of the first data structure that corresponds to the at least first combination with a time stamp value corresponding to a time at which the heartbeat communication was received at one of the storage ports,
wherein the determining includes determining from the first data structure that one or more combinations of a host port and a storage port have I/O connectivity currently enabled between the host port and storage device, but no I/O connectivity currently enabled between the host port and storage device for any of the plurality of storage devices.

10. The system of claim 9 , wherein maintaining the first data structure includes recording, for each combination of a host port and a storage port having an entry in the data structure, a time stamp value of a last heartbeat communication, if any, received for each combination.

11. The system of claim 9 , the method further comprising:
sorting two or more of the plurality of entries based at least in part on the time stamp values of the two or more entries.

12. The system of claim 9 , wherein each entry of the data structure was previously created when the host port corresponding to the entry logged into the storage port corresponding to the entry.

13. The system of claim 8 , the method further comprising:
one or more multi-path drivers of the one or more host systems sending the plurality of heartbeat communications.

14. The system of claim 8 , the method further comprising:
determining from the heartbeat communications that one or more combinations of a host port and a storage port do not have I/O connectivity currently enabled between the host port and storage device.

15. One or more non-transitory computer-readable media for a storage system of a storage network including one or more host systems coupled to the storage system, wherein the storage system includes a plurality of storage devices and the computer-readable media has software stored thereon defining a method, the software comprising:
executable code that receives a plurality of heartbeat communications at one or more storage ports of the storage system from the one or more host systems, each heartbeat communication indicative of current I/O connectivity between a combination of a respective host port of the one or more host systems and a respective one of the storage ports; and
executable code that determines from the heartbeat communications that, for each of one or more combinations of a host port and a storage port defining an I/O path: the combination has I/O connectivity currently enabled between the host port and the storage port on the I/O path, but no I/O connectivity currently enabled for any one of the plurality of storage devices over the I/O path defined between the host port and the storage port.

16. The one or more non-transitory computer-readable media of claim 8 , the software further comprising:
executable code that maintains a first data structure on the storage system, the first data structure including a plurality of entries, each entry corresponding to a combination of a storage port of the

Assignees

• Emc Ip Holding Co Llc

Inventors

• Specht Michael E
• Rao Vinay G
• George Subin
• Don Arieh

Classifications

• H04L43/106 Primary

  using time related information in packets, e.g. by adding timestamps · CPC title

• H04L43/0811 Primary

  by checking connectivity · CPC title

• H04L67/1097

  for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS] · CPC title

• H04L45/24

  Multipath · CPC title

• H04L49/30

  Peripheral units, e.g. input or output ports · CPC title