Bug 960989

Summary: [sanlock] Provide a command to request the release of a resource currently held by another host/pid
Product: Red Hat Enterprise Linux 6 Reporter: Federico Simoncelli <fsimonce>
Component: sanlockAssignee: David Teigland <teigland>
Status: CLOSED ERRATA QA Contact: Leonid Natapov <lnatapov>
Severity: unspecified Docs Contact:
Priority: medium    
Version: 6.5CC: cluster-maint, cpelland, fsimonce, iheim, tlavigne
Target Milestone: rcKeywords: Rebase
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: sanlock-2.8-1 Doc Type: Rebase: Bug Fixes and Enhancements
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2013-11-21 11:48:38 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 883504    

Description Federico Simoncelli 2013-05-08 13:17:07 UTC
Description of problem:
Sanlock should provide a way to request the release of a resource currently held by another host.

Additional info:
This feature is currently implemented in the daemon but it's not exposed through the python bindings. A patch has been posted upstream:

https://lists.fedorahosted.org/pipermail/sanlock-devel/2013-May/000367.html

As far as the use case is concerned this feature is probably dependent on some previous patches:

9863624 python: return lease version in read_resource
0ce413a python: add the versioning support to acquire

The API call named "request" (for consistency with the name exposed by the C API) is defined as follows:

request(lockspace, resource, disks [, action=REQ_RELEASE, version=0])

The possible values for action are REQ_RELEASE and REQ_FORCE (which escalates to sigkill if the regular graceful release is not satisfied).

Comment 2 yeylon@redhat.com 2013-07-01 20:14:16 UTC
how do we test this?

Comment 3 Federico Simoncelli 2013-07-01 21:15:43 UTC
(In reply to Yaniv Eylon from comment #2)
> how do we test this?

Using a shared storage, two hosts and sanlock commands (even better python scripts). We'll add the technical details (e.g. sanlock commands or python scripts) ASAP.

Comment 4 David Teigland 2013-07-01 21:48:37 UTC
Here is a sequence of commands to test the capability without the need for a separate test program.  It uses a shared vg "test" with a shared lv "test".


host1,2: service wdmd start
host1,2: service sanlock start

host1:
lvcreate -n test -L1G test
sanlock client init -s test:0:/dev/test/test:0
sanlock client init -r test:test:/dev/test/test:1048576

host1: sanlock client add_lockspace -s test:1:/dev/test/test:0
host2: sanlock client add_lockspace -s test:2:/dev/test/test:0

host1: sanlock client command -r test:test:/dev/test/test:1048576 -c /bin/sleep 1000

(This acquires the lock then runs "sleep" for 1000 seconds.)

host2: sanlock client request -r test:test:/dev/test/test:1048576:2 -f 1

(After this, the "sleep" on host1 should be killed within 30 seconds.)

Comment 7 Leonid Natapov 2013-08-28 12:14:07 UTC
sanlock-2.8-1.el6.x86_64.
tested according to instructions in comment #4.

Comment 9 errata-xmlrpc 2013-11-21 11:48:38 UTC
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

http://rhn.redhat.com/errata/RHBA-2013-1632.html