Red Hat Bugzilla – Bug 1255830
FAILED assert(m_seed < old_pg_num) in librbd when increasing placement groups
Last modified: 2017-07-30 11:27:35 EDT
Jason, I tried the following and it worked fine, please let me know if there is any further validation required. Below are the 2 use case by which i verified. 1st Use case: 1. Created rbd image, took snapshot and cloned it. 2. Mapped it to a VM and installed OS on top of it. 3. Started writing some IO using dd, then abruptly shutdown the VM. Meanwhile i opened a watch instance on that image, while shutting down the VM. rbd watch --pool Tanay-RBD testingClone_new1 While all this was happening, i incremented the pg_num and pgp_num in a loop (50 times )for that pool. I didn't see any FAILED assert error message in watch/log. Only thing i am seeing in watch is: [root@cephqe3 ceph-config]# rbd watch --pool Tanay-RBD testingClone_new1 press enter to exit... testingClone_new1 received notification: notify_id=3435973836800, cookie=48502592, notifier_id=1467375, bl.length=26 testingClone_new1 received notification: notify_id=3435973836801, cookie=48502592, notifier_id=1468015, bl.length=26 testingClone_new1 received notification: notify_id=3453153705986, cookie=48502592, notifier_id=1469010, bl.length=26 2nd Use case is: 1. Created rbd image, took snapshot and cloned it. 2. Exercised librbd api calls, image.write and image.read Meanwhile i opened a watch instance on that image. rbd watch --pool Tanay-RBD testingClone_new3 While all this was happening, i incremented the pg_num and pgp_num in a loop (50 times )for that pool Thanks.
Your first test showed that the watch was still established since you received messages. For future reference, you can just use 'rados -p <pool> listwatchers <image name>.rbd' (assuming RBD image format 1 for ease of header lookup) to verify that the image still has a valid watch after resizing the PG.
Marking this Bug as Verified.
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. https://access.redhat.com/errata/RHSA-2015:2512
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. https://access.redhat.com/errata/RHSA-2015:2066