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<div class="moz-cite-prefix"> I patched python source managers.py
to retry recv() after EINTR, supervdsm works well and the issue
gone.<br>
Even declared in python doc that:"only the main thread
can set a new signal handler, and the main thread will be the only
one to
receive signals (this is enforced by the Python <a
class="reference internal"
href="http://docs.python.org/2/library/signal.html#module-signal"
title="signal: Set handlers for asynchronous events."><tt
class="xref py py-mod docutils literal"><span class="pre">signal</span></tt></a>
module, even
if the underlying thread implementation supports sending signals
to
individual threads).
"(<a class="moz-txt-link-freetext" href="http://docs.python.org/2/library/signal.html">http://docs.python.org/2/library/signal.html</a>)<br>
But according to my test script bellow, the child process
forker event if it is not the main thread, also got SIGCHILD, Will
it be a python BUG or feature?<br>
I agree with Mark maybe we should use synchronised way to deal
with child process instead of signal handler. <br>
<pre>import threading</pre>
<pre>import signal</pre>
<pre>import time</pre>
<pre>import os</pre>
<pre>from multiprocessing import Process,Pipe</pre>
<pre>
</pre>
<pre>def _zombieReaper(signum, frame):</pre>
<pre> print 'sigchild!!!'
def child():</pre>
<pre> time.sleep(5)</pre>
<pre>
def sleepThread():</pre>
<pre> proc = Process(target=child)</pre>
<pre> proc.start()</pre>
<pre> pip,pop = Pipe()</pre>
<pre> pip.recv()<----------<font color="#6666cc">This line will get IOError.EINTR by SIGCHLD</font></pre>
<pre>
def main():</pre>
<pre> signal.signal(signal.SIGCHLD, _zombieReaper)
</pre>
<pre> servThread = threading.Thread(target = sleepThread)</pre>
<pre> servThread.setDaemon(True)</pre>
<pre> servThread.start()</pre>
<pre> time.sleep(30)</pre>
<pre>
if __name__ == '__main__':</pre>
<pre> main()</pre>
On 01/25/2013 03:20 PM, Mark Wu wrote:<br>
</div>
<blockquote cite="mid:51023254.3070204@linux.vnet.ibm.com"
type="cite">Great work!
<br>
The default action for SIGCHLD is ignore, so there's no problems
reported before a signal handler is installed by zombie reaper.
<br>
But I still have one problem: the python multiprocessing.manager
code is running a new thread and according to the implementation
of python's signal, only the main thread can receive the signal.
<br>
So how is the signal delivered to the server thread?
<br>
<br>
<br>
On Fri 25 Jan 2013 12:30:39 PM CST, Royce Lv wrote:
<br>
<blockquote type="cite">
<br>
Hi,
<br>
I reproduced this issue, and I believe it's a python bug.
<br>
1. How to reproduce:
<br>
with the test case attached, put it under
/usr/share/vdsm/tests/,
<br>
run #./run_tests.sh superVdsmTests.py
<br>
and this issue will be reproduced.
<br>
2.Log analyse:
<br>
We notice a strange pattern in this log: connectStorageServer
be
<br>
called twice, first supervdsm call succeed, second fails becasue
of
<br>
validateAccess().
<br>
That is because for the first call validateAccess returns
normally
<br>
and leave a child there, when the second validateAccess call
arrives
<br>
and multirprocessing manager is receiving the method message, it
is
<br>
just the time first child exit and SIGCHLD comming, this signal
<br>
interrupted multiprocessing receive system call, python
managers.py
<br>
should handle INTR and retry recv() like we do in vdsm but it's
not,
<br>
so the second one raise error.
<br>
>Thread-18::DEBUG::2013-01-22
10:41:03,570::misc::85::Storage.Misc.excCmd::(<lambda>)
'/usr/bin/sudo -n /bin/mount -t nfs -o
soft,nosharecache,timeo=600,retrans=6,nfsvers=3
192.168.0.1:/ovirt/silvermoon
/rhev/data-center/mnt/192.168.0.1:_ovirt_silvermoon' (cwd None)
<br>
>Thread-18::DEBUG::2013-01-22
10:41:03,607::misc::85::Storage.Misc.excCmd::(<lambda>)
'/usr/bin/sudo -n /bin/mount -t nfs -o
soft,nosharecache,timeo=600,retrans=6,nfsvers=3
192.168.0.1:/ovirt/undercity
/rhev/data-center/mnt/192.168.0.1:_ovirt_undercity' (cwd None)
<br>
>Thread-18::ERROR::2013-01-22
10:41:03,627::hsm::2215::Storage.HSM::(connectStorageServer)
Could not connect to storageServer
<br>
>Traceback (most recent call last):
<br>
> File "/usr/share/vdsm/storage/hsm.py", line 2211, in
connectStorageServer
<br>
> conObj.connect()
<br>
> File "/usr/share/vdsm/storage/storageServer.py", line 303,
in connect
<br>
> return self._mountCon.connect()
<br>
> File "/usr/share/vdsm/storage/storageServer.py", line 209,
in connect
<br>
>
fileSD.validateDirAccess(self.getMountObj().getRecord().fs_file)
<br>
> File "/usr/share/vdsm/storage/fileSD.py", line 55, in
validateDirAccess
<br>
> (os.R_OK | os.X_OK))
<br>
> File "/usr/share/vdsm/supervdsm.py", line 81, in __call__
<br>
> return callMethod()
<br>
> File "/usr/share/vdsm/supervdsm.py", line 72, in
<lambda>
<br>
> **kwargs)
<br>
> File "<string>", line 2, in validateAccess
<br>
> File "/usr/lib64/python2.6/multiprocessing/managers.py",
line 740, in _callmethod
<br>
> raise convert_to_error(kind, result)
<br>
the vdsm side receive RemoteError because of supervdsm server
<br>
multiprocessing manager raise error KIND='TRACEBACK'
<br>
>RemoteError:
<br>
The upper part is the trace back from the client side, the
following
<br>
part is from server side:
<br>
>---------------------------------------------------------------------------
<br>
>Traceback (most recent call last):
<br>
> File "/usr/lib64/python2.6/multiprocessing/managers.py",
line 214, in serve_client
<br>
> request = recv()
<br>
>IOError: [Errno 4] Interrupted system call
<br>
>---------------------------------------------------------------------------
<br>
<br>
Corresponding Python source code:managers.py(Server side)
<br>
def serve_client(self, conn):
<br>
'''
<br>
Handle requests from the proxies in a particular
process/thread
<br>
'''
<br>
util.debug('starting server thread to service %r',
<br>
threading.current_thread().name)
<br>
recv = conn.recv
<br>
send = conn.send
<br>
id_to_obj = self.id_to_obj
<br>
while not self.stop:
<br>
try:
<br>
methodname = obj = None
<br>
request = recv()<------------------this line
been interrupted by SIGCHLD
<br>
ident, methodname, args, kwds = request
<br>
obj, exposed, gettypeid = id_to_obj[ident]
<br>
if methodname not in exposed:
<br>
raise AttributeError(
<br>
'method %r of %r object is not in
exposed=%r' %
<br>
(methodname, type(obj), exposed)
<br>
)
<br>
function = getattr(obj, methodname)
<br>
try:
<br>
res = function(*args, **kwds)
<br>
except Exception, e:
<br>
msg = ('#ERROR', e)
<br>
else:
<br>
typeid = gettypeid and
gettypeid.get(methodname, None)
<br>
if typeid:
<br>
rident, rexposed = self.create(conn,
typeid, res)
<br>
token = Token(typeid, self.address,
rident)
<br>
msg = ('#PROXY', (rexposed, token))
<br>
else:
<br>
msg = ('#RETURN', res)
<br>
except AttributeError:
<br>
if methodname is None:
<br>
msg = ('#TRACEBACK', format_exc())
<br>
else:
<br>
try:
<br>
fallback_func =
self.fallback_mapping[methodname]
<br>
result = fallback_func(
<br>
self, conn, ident, obj, *args,
**kwds
<br>
)
<br>
msg = ('#RETURN', result)
<br>
except Exception:
<br>
msg = ('#TRACEBACK', format_exc())
<br>
<br>
except EOFError:
<br>
util.debug('got EOF -- exiting thread serving
%r',
<br>
threading.current_thread().name)
<br>
sys.exit(0)
<br>
<br>
except Exception:<------does not handle
IOError,INTR here should retry recv()
<br>
msg = ('#TRACEBACK', format_exc())
<br>
<br>
<br>
3. Actions we will take:
<br>
(1)As a work round we can first remove the zombie reaper from
<br>
supervdsm server
<br>
(2)I'll see whether python has a fixed version for this
<br>
(3)Yaniv is working on changing vdsm/svdsm communication channel
to
<br>
pipe and handle it ourselves, I believe we'll get rid of this
with
<br>
that properly handled.
<br>
<br>
<br>
On 01/25/2013 06:00 AM, Dead Horse wrote:
<br>
<blockquote type="cite">Tried some manual edits to SD states in
the dbase. The net result was
<br>
I was able to get a node active. However as reconstructing the
master
<br>
storage domain kicked in it was unable to do so. It was also
not able
<br>
to recognize the other SD with similar failure modes to the
<br>
unrecognized master above. Guessing the newer VDSM version
borked
<br>
things pretty good. So being as this is a test harness and the
SD
<br>
data is not worth saving I just smoked the all SD. I ran
<br>
engine-cleanup and started from fresh and all is well now.
<br>
<br>
- DHC
<br>
<br>
<br>
On Thu, Jan 24, 2013 at 11:53 AM, Dead Horse
<br>
<<a class="moz-txt-link-abbreviated" href="mailto:deadhorseconsulting@gmail.com">deadhorseconsulting@gmail.com</a>
<br>
<a class="moz-txt-link-rfc2396E" href="mailto:deadhorseconsulting@gmail.com"><mailto:deadhorseconsulting@gmail.com></a>> wrote:
<br>
<br>
This test harness setup here consists of two servers tied
to NFS
<br>
storage via IB (NFS mounts are via IPoIB, NFS over RDMA is
<br>
disabled) . All storage domains are NFS. The issue does
occur
<br>
with both servers on when attempting to bring them out of
<br>
maintenance mode with the end result being non-operational
due to
<br>
storage attach fail.
<br>
<br>
The current issue is now that with a working older commit
the
<br>
master storage domain is "stuck" in state "locked" and I
see the
<br>
secondary issue wherein VDSM cannot seem to find or
contact the
<br>
master storage domain even though it is there. I am can
mount the
<br>
master storage domain manually and and all content appears
to be
<br>
accounted for accordingly on either host.
<br>
<br>
Here is the current contents of the master storage domain
metadata:
<br>
CLASS=Data
<br>
DESCRIPTION=orgrimmar
<br>
IOOPTIMEOUTSEC=1
<br>
LEASERETRIES=3
<br>
LEASETIMESEC=5
<br>
LOCKPOLICY=
<br>
LOCKRENEWALINTERVALSEC=5
<br>
MASTER_VERSION=417
<br>
POOL_DESCRIPTION=Azeroth
<br>
POOL_DOMAINS=0549ee91-4498-4130-8c23-4c173b5c0959:Active,d8b55105-c90a-465d-9803-8130da9a671e:Active,67534cca-1327-462a-b455-a04464084b31:Active,c331a800-839d-4d23-9059-870a7471240a:Active,f8984825-ff8d-43d9-91db-0d0959f8bae9:Active,c434056e-96be-4702-8beb-82a408a5c8cb:Active,f7da73c7-b5fe-48b6-93a0-0c773018c94f:Active,82e3b34a-6f89-4299-8cd8-2cc8f973a3b4:Active,e615c975-6b00-469f-8fb6-ff58ae3fdb2c:Active,5bc86532-55f7-4a91-a52c-fad261f322d5:Active,1130b87a-3b34-45d6-8016-d435825c68ef:Active<br>
POOL_SPM_ID=1
<br>
POOL_SPM_LVER=6
<br>
POOL_UUID=f90a0d1c-06ca-11e2-a05b-00151712f280
<br>
REMOTE_PATH=192.168.0.1:/ovirt/orgrimmar
<br>
ROLE=Master
<br>
SDUUID=67534cca-1327-462a-b455-a04464084b31
<br>
TYPE=NFS
<br>
VERSION=3
<br>
_SHA_CKSUM=1442bb078fd8c9468d241ff141e9bf53839f0721
<br>
<br>
So now with the older working commit I now get this the
<br>
"StoragePoolMasterNotFound: Cannot find master domain"
error
<br>
(prior details above when I worked backwards to that
commit)
<br>
<br>
This is odd as the nodes can definitely reach the master
storage
<br>
domain:
<br>
<br>
showmount from one of the el6.3 nodes:
<br>
[root@kezan ~]# showmount -e 192.168.0.1
<br>
Export list for 192.168.0.1 <a class="moz-txt-link-rfc2396E" href="http://192.168.0.1"><http://192.168.0.1></a>:
<br>
/ovirt/orgrimmar 192.168.0.0/16
<a class="moz-txt-link-rfc2396E" href="http://192.168.0.0/16"><http://192.168.0.0/16></a>
<br>
<br>
mount/ls from one of the nodes:
<br>
[root@kezan ~]# mount 192.168.0.1:/ovirt/orgrimmar /mnt
<br>
[root@kezan ~]# ls -al
<br>
/mnt/67534cca-1327-462a-b455-a04464084b31/dom_md/
<br>
total 1100
<br>
drwxr-xr-x 2 vdsm kvm 4096 Jan 24 11:44 .
<br>
drwxr-xr-x 5 vdsm kvm 4096 Oct 19 16:16 ..
<br>
-rw-rw---- 1 vdsm kvm 1048576 Jan 19 22:09 ids
<br>
-rw-rw---- 1 vdsm kvm 0 Sep 25 00:46 inbox
<br>
-rw-rw---- 1 vdsm kvm 2097152 Jan 10 13:33 leases
<br>
-rw-r--r-- 1 vdsm kvm 903 Jan 10 13:39 metadata
<br>
-rw-rw---- 1 vdsm kvm 0 Sep 25 00:46 outbox
<br>
<br>
<br>
- DHC
<br>
<br>
<br>
<br>
On Thu, Jan 24, 2013 at 7:51 AM, ybronhei
<<a class="moz-txt-link-abbreviated" href="mailto:ybronhei@redhat.com">ybronhei@redhat.com</a>
<br>
<a class="moz-txt-link-rfc2396E" href="mailto:ybronhei@redhat.com"><mailto:ybronhei@redhat.com></a>> wrote:
<br>
<br>
On 01/24/2013 12:44 AM, Dead Horse wrote:
<br>
<br>
I narrowed down on the commit where the originally
<br>
reported issue crept in:
<br>
commitfc3a44f71d2ef202cff18d7203b9e4165b546621building
<br>
and testing with
<br>
<br>
this commit or subsequent commits yields the
original issue.
<br>
<br>
Interesting.. it might be related to this commit and
we're
<br>
trying to reproduce it.
<br>
<br>
Did you try to remove that code and run again? does it
work
<br>
without the additional of zombieReaper?
<br>
does the connectivity to the storage work well? when
you run
<br>
'ls' on the mounted folder you get see the files
without a
<br>
long delay ? it might related to too long timeout when
<br>
validating access to this mount..
<br>
we work on that.. any additional info can help
<br>
<br>
Thanks.
<br>
<br>
<br>
- DHC
<br>
<br>
<br>
On Wed, Jan 23, 2013 at 3:56 PM, Dead Horse
<br>
<<a class="moz-txt-link-abbreviated" href="mailto:deadhorseconsulting@gmail.com">deadhorseconsulting@gmail.com</a>
<br>
<a class="moz-txt-link-rfc2396E" href="mailto:deadhorseconsulting@gmail.com"><mailto:deadhorseconsulting@gmail.com></a>>wrote:
<br>
<br>
Indeed reverting back to an older vdsm clears
up the
<br>
above issue. However
<br>
now I the issue is see is:
<br>
Thread-18::ERROR::2013-01-23
<br>
15:50:42,885::task::833::TaskManager.Task::(_setError)
<br>
Task=`08709e68-bcbc-40d8-843a-d69d4df40ac6`::Unexpected
<br>
error
<br>
<br>
Traceback (most recent call last):
<br>
File "/usr/share/vdsm/storage/task.py",
line 840,
<br>
in _run
<br>
return fn(*args, **kargs)
<br>
File "/usr/share/vdsm/logUtils.py", line
42, in
<br>
wrapper
<br>
res = f(*args, **kwargs)
<br>
File "/usr/share/vdsm/storage/hsm.py", line
923,
<br>
in connectStoragePool
<br>
masterVersion, options)
<br>
File "/usr/share/vdsm/storage/hsm.py", line
970,
<br>
in _connectStoragePool
<br>
res = pool.connect(hostID, scsiKey,
msdUUID,
<br>
masterVersion)
<br>
File "/usr/share/vdsm/storage/sp.py", line
643, in
<br>
connect
<br>
self.__rebuild(msdUUID=msdUUID,
<br>
masterVersion=masterVersion)
<br>
File "/usr/share/vdsm/storage/sp.py", line
1167,
<br>
in __rebuild
<br>
self.masterDomain =
<br>
self.getMasterDomain(msdUUID=msdUUID,
<br>
masterVersion=masterVersion)
<br>
File "/usr/share/vdsm/storage/sp.py", line
1506,
<br>
in getMasterDomain
<br>
raise
se.StoragePoolMasterNotFound(self.spUUID,
<br>
msdUUID)
<br>
StoragePoolMasterNotFound: Cannot find master
domain:
<br>
'spUUID=f90a0d1c-06ca-11e2-a05b-00151712f280,
<br>
msdUUID=67534cca-1327-462a-b455-a04464084b31'
<br>
Thread-18::DEBUG::2013-01-23
<br>
15:50:42,887::task::852::TaskManager.Task::(_run)
<br>
Task=`08709e68-bcbc-40d8-843a-d69d4df40ac6`::Task._run:
<br>
08709e68-bcbc-40d8-843a-d69d4df40ac6
<br>
('f90a0d1c-06ca-11e2-a05b-00151712f280', 2,
<br>
'f90a0d1c-06ca-11e2-a05b-00151712f280',
<br>
'67534cca-1327-462a-b455-a04464084b31', 433)
{}
<br>
failed - stopping task
<br>
<br>
This is with vdsm built from
<br>
commit25a2d8572ad32352227c98a86631300fbd6523c1
<br>
- DHC
<br>
<br>
<br>
On Wed, Jan 23, 2013 at 10:44 AM, Dead Horse
<
<br>
<a class="moz-txt-link-abbreviated" href="mailto:deadhorseconsulting@gmail.com">deadhorseconsulting@gmail.com</a>
<br>
<a class="moz-txt-link-rfc2396E" href="mailto:deadhorseconsulting@gmail.com"><mailto:deadhorseconsulting@gmail.com></a>> wrote:
<br>
<br>
VDSM was built from:
<br>
commit
166138e37e75767b32227746bb671b1dab9cdd5e
<br>
<br>
Attached is the full vdsm log
<br>
<br>
I should also note that from engine
perspective
<br>
it sees the master
<br>
storage domain as locked and the others as
unknown.
<br>
<br>
<br>
On Wed, Jan 23, 2013 at 2:49 AM, Dan
Kenigsberg
<br>
<<a class="moz-txt-link-abbreviated" href="mailto:danken@redhat.com">danken@redhat.com</a>
<a class="moz-txt-link-rfc2396E" href="mailto:danken@redhat.com"><mailto:danken@redhat.com></a>>wrote:
<br>
<br>
On Tue, Jan 22, 2013 at 04:02:24PM
-0600,
<br>
Dead Horse wrote:
<br>
<br>
Any ideas on this one? (from VDSM
log):
<br>
Thread-25::DEBUG::2013-01-22
<br>
15:35:29,065::BindingXMLRPC::914::vds::(wrapper)
<br>
client
<br>
<br>
[3.57.111.30]::call
<br>
<br>
getCapabilities with () {}
<br>
Thread-25::ERROR::2013-01-22
<br>
15:35:29,113::netinfo::159::root::(speed)
<br>
cannot read ib0 speed
<br>
Traceback (most recent call last):
<br>
File
<br>
"/usr/lib64/python2.6/site-packages/vdsm/netinfo.py",
<br>
line 155,
<br>
<br>
in
<br>
<br>
speed
<br>
s =
<br>
int(file('/sys/class/net/%s/speed'
%
<br>
dev).read())
<br>
IOError: [Errno 22] Invalid
argument
<br>
<br>
Causes VDSM to fail to attach
storage
<br>
<br>
<br>
I doubt that this is the cause of the
<br>
failure, as vdsm has always
<br>
reported "0" for ib devices, and still
is.
<br>
<br>
it happens only when you call to getCapabilities.. so
it
<br>
doesn't related to the flow, and it can't effect the
storage.
<br>
Dan: I guess this is not the issue but why is the
IOError?
<br>
<br>
<br>
Does a former version works with your
Engine?
<br>
Could you share more of your vdsm.log?
I
<br>
suppose the culprit lies in one
<br>
one of the storage-related commands,
not in
<br>
statistics retrieval.
<br>
<br>
<br>
Engine side sees:
<br>
ERROR
<br>
[org.ovirt.engine.core.bll.storage.NFSStorageHelper]
<br>
(QuartzScheduler_Worker-96)
[553ef26e]
<br>
The connection with details
<br>
192.168.0.1:/ovirt/ds failed
because of
<br>
error code 100 and error
<br>
<br>
message
<br>
<br>
is: general exception
<br>
2013-01-22 15:35:30,160 INFO
<br>
[org.ovirt.engine.core.bll.SetNonOperationalVdsCommand]
<br>
(QuartzScheduler_Worker-96)
[1ab78378]
<br>
Running command:
<br>
SetNonOperationalVdsCommand
internal:
<br>
true. Entities affected : ID:
<br>
8970b3fe-1faf-11e2-bc1f-00151712f280
<br>
Type: VDS
<br>
2013-01-22 15:35:30,200 INFO
<br>
[org.ovirt.engine.core.vdsbroker.SetVdsStatusVDSCommand]
<br>
(QuartzScheduler_Worker-96)
[1ab78378] START,
<br>
SetVdsStatusVDSCommand(HostName =
kezan,
<br>
HostId =
<br>
8970b3fe-1faf-11e2-bc1f-00151712f280,
<br>
status=NonOperational,
<br>
nonOperationalReason=STORAGE_DOMAIN_UNREACHABLE),
<br>
log id: 4af5c4cd
<br>
2013-01-22 15:35:30,211 INFO
<br>
[org.ovirt.engine.core.vdsbroker.SetVdsStatusVDSCommand]
<br>
(QuartzScheduler_Worker-96)
[1ab78378]
<br>
FINISH, SetVdsStatusVDSCommand,
<br>
<br>
log
<br>
<br>
id: 4af5c4cd
<br>
2013-01-22 15:35:30,242 ERROR
<br>
[org.ovirt.engine.core.dal.dbbroker.auditloghandling.AuditLogDirector]
<br>
(QuartzScheduler_Worker-96)
[1ab78378]
<br>
Try to add duplicate audit log
<br>
values with the same name. Type:
<br>
VDS_SET_NONOPERATIONAL_DOMAIN.
Value:
<br>
storagepoolname
<br>
<br>
Engine = latest master
<br>
VDSM = latest master
<br>
<br>
<br>
Since "latest master" is an unstable
<br>
reference by definition, I'm sure
<br>
that History would thank you if you
post the
<br>
exact version (git hash?)
<br>
of the code.
<br>
<br>
node = el6
<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
_______________________________________________
<br>
Users mailing list
<br>
<a class="moz-txt-link-abbreviated" href="mailto:Users@ovirt.org">Users@ovirt.org</a> <a class="moz-txt-link-rfc2396E" href="mailto:Users@ovirt.org"><mailto:Users@ovirt.org></a>
<br>
<a class="moz-txt-link-freetext" href="http://lists.ovirt.org/mailman/listinfo/users">http://lists.ovirt.org/mailman/listinfo/users</a>
<br>
<br>
<br>
<br>
--
<br>
Yaniv Bronhaim.
<br>
RedHat, Israel
<br>
09-7692289
<br>
054-7744187
<br>
<br>
<br>
<br>
</blockquote>
<br>
<br>
<br>
<br>
_______________________________________________
<br>
Users mailing list
<br>
<a class="moz-txt-link-abbreviated" href="mailto:Users@ovirt.org">Users@ovirt.org</a>
<br>
<a class="moz-txt-link-freetext" href="http://lists.ovirt.org/mailman/listinfo/users">http://lists.ovirt.org/mailman/listinfo/users</a>
<br>
</blockquote>
<br>
<br>
</blockquote>
<br>
<br>
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