Container storage migration

Patent metadata

Field	Value
Publication number	US-9852137-B2
Application number	US-201514862786-A
Country	US
Kind code	B2
Filing date	Sep 23, 2015
Priority date	Sep 23, 2015
Publication date	Dec 26, 2017
Grant date	Dec 26, 2017

Abstract

Methods, systems, and computer program products for container storage migration are provided herein. A computer-implemented method includes provisioning a copy-on-write union filesystem on the target host with (i) one or more network filesystem-mounted directories from the source host set to read-only and (ii) at least one directory set to read-write; identifying one or more files that have been (i) updated by a given container and (ii) copied over by the copy-on-write union filesystem; removing the one or more identified files from a directory path on the target host; copying, from the source host into the directory path on the target host, each of one or more files that have not been updated by the given container; merging the copy-on-write union filesystem and the directory path on the target host; and initiating the given container on the target host based on the merging.

First claim

What is claimed is:

1. A computer-implemented method for migrating a container from a source host to a target host, comprising:
provisioning a copy-on-write union filesystem on the target host with (i) one or more network filesystem-mounted directories from the source host set to read-only and (ii) at least one directory set to read-write;
identifying one or more files that have been (i) updated by a given container and (ii) copied over by the copy-on-write union filesystem;
removing the one or more identified files from a directory path on the target host;
copying, from the source host into the directory path on the target host, each of one or more files that have not been updated by the given container;
merging the copy-on-write union filesystem and the directory path on the target host; and
initiating the given container on the target host based on said merging;
wherein said steps are carried out by at least one computing device.

2. The computer-implemented method of claim 1 , wherein said copying is performed as a background operation.

3. The computer-implemented method of claim 1 , comprising:
exporting at least one root filesystem directory from the source host to the target host.

4. The computer-implemented method of claim 1 , comprising:
exporting at least one data volume directory from the source host to the target host.

5. The computer-implemented method of claim 1 , comprising:
creating a directory to receive one or more write operations from the source host.

6. The computer-implemented method of claim 5 , comprising:
mounting the one or more write operations that are exported over a network filesystem on the source host into the created directory.

7. The computer-implemented method of claim 1 , wherein said provisioning comprises using an advanced multi-layered unification filesystem.

8. The computer-implemented method of claim 1 , wherein said identifying comprises using a filesystem monitoring tool.

9. The computer-implemented method of claim 1 , wherein said given container comprises a new container launched prior to said identifying.

10. The computer-implemented method of claim 1 , wherein said given container comprises a container derived from the source host that is restarted after migration from the source host.

11. The computer-implemented method of claim 10 , wherein the container derived from the source host includes the copy-on-write union filesystem as data volume.

12. The computer-implemented method of claim 1 , wherein said removing is carried out by a replicator module.

13. The computer-implemented method of claim 1 , wherein said copying is carried out by a replicator module.

14. A computer program product for migrating a container from a source host to a target host, the computer program product comprising a computer readable storage medium having program instructions embodied therewith, the program instructions executable by a device to cause the device to:
provision a copy-on-write union filesystem on the target host with (i) one or more network filesystem-mounted directories from the source host set to read-only and (ii) at least one directory set to read-write;
identify one or more files that have been (i) updated by a given container and (ii) copied over by the copy-on-write union filesystem;
remove the one or more identified files from a directory path on the target host;
copy, from the source host into the directory path on the target host, each of one or more files that have not been updated by the given container;
merge the copy-on-write union filesystem and the directory path on the target host; and
initiate the given container on the target host based on said merging.

15. The computer program product of claim 14 , wherein the program instructions executable by a computing device further cause the computing device to:
create a directory to receive one or more write operations from the source host.

16. The computer program product of claim 15 , wherein the program instructions executable by a computing device further cause the computing device to:
mount the one or more write operations that are exported over a network filesystem on the source host into the created directory.

17. The computer program product of claim 14 , wherein said given container comprises a new container launched prior to said identifying and/or a container derived from the source host that is restarted after migration from the source host.

18. A system for migrating a container from a source host to a target host comprising:
a memory; and
at least one processor coupled to the memory and configured for:
provisioning a copy-on-write union filesystem on the target host with (i) one or more network filesystem-mounted directories from the source host set to read-only and (ii) at least one directory set to read-write;
identifying one or more files that have been (i) updated by a given container and (ii) copied over by the copy-on-write union filesystem;
removing the one or more identified files from a directory path on the target host;
copying, from the source host into the directory path on the target host, each of one or more files that have not been updated by the given container;
merging the copy-on-write union filesystem and the directory path on the target host; and
initiating the given container on the target host based on said merging.

19. A computer-implemented method, comprising:
creating a write-able directory on a local filesystem;
mounting the write-able directory with a network filesystem directory exported from a host source, wherein the network filesystem directory is mounted as read-only;
creating a layered filesystem on a container, wherein the layered filesystem comprises (i) a single layer that is write-able and (ii) one or more additional layers that are each read-only;
establishing a symbolic link on the single layer that is write-able in the layered filesystem to the mounted network filesystem directory; and
instantiating the container based on said symbolic link;
wherein said steps are carried out by at least one computing device.

20. The computer-implemented method of claim 19 , wherein the network filesystem directory exported from the host source comprises a single layer that is writeable in a layered filesystem on a container in the host source.

Assignees

• IBM

Inventors

• Mann Vijay
• Nadgowda Shripad J

Classifications

• G06F3/0604

  Improving or facilitating administration, e.g. storage management · CPC title

• G06F3/0629

  Configuration or reconfiguration of storage systems · CPC title

• G06F3/0647

  Migration mechanisms · CPC title

• G06F3/067

  Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS] · CPC title

• G06F17/30079 Primary

  Physics · mapped topic