On 07/30/2014 12:07 PM, Aanchal Agrawal wrote:
Hi,
We found a case(bug?) in ceph mon code, where in, an attempt to start a non-existing monitor is
throwing up a levelDB error saying "failed to create new leveldb store", instead we
thought an appropriate message say "No Monitor present with that id" would do, by
checking for the monitor existence way ahead.
It seems that 'mon_exists()' checks for the existence of the mon data
directory(via 'mon_data_exists()') and also for the non-empty nature of that
directory(via 'mon_data_empty()'). The fix seemed pretty simple, as to flag the
appropriate message if 'mon_data_exists()' were to set 'exists' to 'false', in
case mkfs is not set.
The other behavior that we are seeking clarity, again in case of mkfs not being set is,
if 'mon_data_exists()' sets 'exists' to 'true' and 'mon_data_empty()' sets 'exists' to
'false' (meaning the mon data directory is present, but it is empty), then the current
code seems to be going ahead in an attempt to open the 'store.db', and when open fails,
it tries to create a new 'store.db' (though mkfs is not set) and eventually gives up
throwing "unable to read magic from mon data".
The questions we had around this were:
1) Though in case of mkfs not being set, what is the reason for creating a new
levelDB store in case an attempt to open the 'store.db' is a failure, as
levelDB anyways seem to be throwing 'magic' error going forward. Are there any
use cases for this scenario?
Separate from Ceph it seems like bad behavior of a daemon to start
creating directories when --mkfs is not supplied.
It should spit our errors about not being able to access it's data
store, but not start creating them without explicitly being told to do so.
2) And also, is it valid to flag "No Monitor present" in case the mon data
directory is existing, but with no data('store.db') in it, in case mkfs is not set?
Thanks,
Aanchal
________________________________
PLEASE NOTE: The information contained in this electronic mail message is
intended only for the use of the designated recipient(s) named above. If the
reader of this message is not the intended recipient, you are hereby notified
that you have received this message in error and that any review,
dissemination, distribution, or copying of this message is strictly prohibited.
If you have received this communication in error, please notify the sender by
telephone or e-mail (as shown above) immediately and destroy any and all copies
of this message in your possession (whether hard copies or electronically
stored copies).
--
To unsubscribe from this list: send the line "unsubscribe ceph-devel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
--
Wido den Hollander
42on B.V.
Ceph trainer and consultant
Phone: +31 (0)20 700 9902
Skype: contact42on
--
To unsubscribe from this list: send the line "unsubscribe ceph-devel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
