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<DIV><FONT face=Arial size=2>Hello ,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Im trying to implement the perfect 2 nodes
cluster(for testing perposes at the moment) and basicly run into 2 problems
</FONT></DIV>
<DIV><FONT face=Arial size=2>wich related to redundency with drbd on the
OSS/OST</FONT></DIV>
<DIV><FONT face=Arial size=2>What im trying to do is configure the 2 nodes in a
way that the 2 backup each other in case 1 crashes</FONT></DIV>
<DIV><FONT face=Arial size=2>The configuration is as follow :</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Node 1 is MGS/MDT on volume drbd0</FONT></DIV>
<DIV><FONT face=Arial size=2>Node 2 is the 1 and only OSS/OST for this cluster
and mounts drbd1</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>At this point its all working , tested clients
mounts from the 2 nodes and it mounts ok</FONT></DIV>
<DIV><FONT face=Arial size=2>To test some failure
situations i tested MGS/MDT failure and OST failures , the
heerbeat V2 is doing its part ok</FONT></DIV>
<DIV><FONT face=Arial size=2>and the other node take over
the resources of the other node e.g mounts the MGS/MDT or the
OST</FONT></DIV>
<DIV><FONT face=Arial size=2>up to now it all works but in such cases that the
other node take over the resource of the other node</FONT></DIV>
<DIV><FONT face=Arial size=2>its not possible to mount a client anymore
, sometimes the client simply cant mount(manualy after changing the
mgs id on the mount command)</FONT></DIV>
<DIV><FONT face=Arial size=2>and sometimes it mounts but cant work with
the volume .</FONT></DIV>
<DIV><FONT face=Arial size=2>After watching the system logs for a while iv
notices a very strange thing , when the OST fail to the other
node</FONT></DIV>
<DIV><FONT face=Arial size=2>it register itslef as new OST with new ID e.g
the original OST id was OST0000 then it mounts as OST0003 and so
on</FONT></DIV>
<DIV><FONT face=Arial size=2>so the client can mount but look for OST0000 insted
of OST0003 cant find it thefor see a cluster with 0 OST's</FONT></DIV>
<DIV><FONT face=Arial size=2>then the mount is ok but he cant work with empty
storage .</FONT></DIV>
<DIV><FONT face=Arial size=2>This behaviour is very strange seens when you
format the OST on drbd volume it replicates its structure to its pair so when
its pair take over</FONT></DIV>
<DIV><FONT face=Arial size=2>the system see it as the same drive much like a
shared storage .</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Iv also tried to format the OST with --failnode
option with no luck , after a node swich over</FONT></DIV>
<DIV><FONT face=Arial size=2>its messing up the all cluster and the client can
or cant mount in ither case it take very long to mount a client</FONT></DIV>
<DIV><FONT face=Arial size=2>even with the -o abort_recov swich on the client
mount command</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>My guess is that it related to lustre cache schema
of storing cluster information upon connection or something with
local</FONT></DIV>
<DIV><FONT face=Arial size=2>configuration on the OOS or MGS/MDT that doesnt get
replicated to the other node</FONT></DIV>
<DIV><FONT face=Arial size=2>i looked for information on lustre doumentations
with not much luck .</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Is my confuguration even possible ? does anybody
run into same issues ?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thanks ,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial
size=2>----------------------------------------------------------<BR>PH(2001)
Internet Services .<BR></FONT></DIV></BODY></HTML>