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<DIV dir=ltr><FONT face=Arial color=#000000 size=2>Hi,</FONT></DIV><FONT
face=Arial size=2>
<DIV dir=ltr><BR>I have found 2 scenarios using FC4 (2.6.13-latest) that cause
LVM problems:</DIV>
<DIV dir=ltr> </DIV>
<DIV dir=ltr>1.</DIV>
<DIV dir=ltr> </DIV>
<DIV dir=ltr>700GB volume, create a snapshot of 100Gb, copy the snap to another
disk, remove the snapshot. The snapshot remove never ends it just hangs. One can
type lvscan, it will display a few LVs and then hang, press Ctrl-C to get out of
that. Ctrl-C does not work with lvremove. No /var/log/messages indicating
cause.</DIV>
<DIV dir=ltr> </DIV>
<DIV dir=ltr>We believe this might happen because the volume copy takes about
8hours, however if I do a snap and then instantly remove it, it works fine.
The 8 hour time frame + plus moderate IO appears to be the problem.</DIV>
<DIV dir=ltr> </DIV>
<DIV dir=ltr> </DIV>
<DIV dir=ltr>2.</FONT></DIV>
<DIV dir=ltr><FONT face=Arial color=#000000 size=2></FONT> </DIV>
<DIV dir=ltr><FONT face=Arial size=2>Labtest: create a 20G volume, create a 8G
snap. From another terminal do dd if=/dev/zero of=/dev/vg/lv bs=1M, after
running for a few minutes remove the snapshot - it cannot be removed until ALL
IO ceases on the original volume.</FONT></DIV>
<DIV dir=ltr><FONT face=Arial size=2></FONT> </DIV>
<DIV dir=ltr><FONT face=Arial size=2>I have tried the development FC4 2.6.14
kernel today and that causes the same problems. lvm2 tools:
lvm2-2.01.08-2.1</FONT></DIV>
<DIV dir=ltr><FONT face=Arial size=2></FONT> </DIV>
<DIV dir=ltr><FONT face=Arial size=2></FONT> </DIV>
<DIV dir=ltr><FONT face=Arial size=2></FONT> </DIV></DIV>
<DIV id=idSignature18434 dir=ltr>
<DIV><FONT face=Arial color=#000000 size=2>
<DIV><FONT face=Verdana size=1>________________________________</FONT> </DIV>
<DIV><FONT face=Verdana size=1>Steffen Plotner</FONT> <BR><FONT face=Verdana
size=1>Systems Administrator/Programmer</FONT> <BR><FONT face=Verdana
size=1>Systems & Networking</FONT> </DIV>
<DIV><FONT face=Verdana size=1>Amherst College</FONT> <BR><FONT face=Verdana
size=1>PO BOX 5000</FONT> <BR><FONT face=Verdana size=1>Amherst, MA
01002-5000</FONT> <BR><FONT face=Verdana size=1>Tel (413) 542-2348</FONT>
<BR><FONT face=Verdana size=1>Fax (413) 542-2626</FONT> <BR><FONT face=Verdana
size=1>Email:<U> </U></FONT><U><FONT face=Verdana color=#0000ff
size=1>swplotner@amherst.edu </FONT></U><BR><FONT face=Verdana
size=1>________________________________</FONT>
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