I was mining on 30 linux shells @ 7-8 hpm average. I had a successful instance which mined a block and I then cloned that instance to 29 others, and eventually reset the wallets on each so there were unique addresses and no chance of redundant mining.
I noticed the bitcoind servers were going down on some of the servers... they were just turned off. Happened about 10 times over past 24 hours. Having not mined anything, I finally looked at the logs, and this is what I saw at the tail end (3 different logs). Am I correct to assume it is crashing just as it finds a block and I have lost 10 blocks!?!
Running ProtoSharesMiner with 1 transactions in block (196 bytes)
testHash 0000966b2881a6a761bb86a2d33fbfb64bd8aee8e039e25faa61d88f8e880f26
Hash Target 0000fff000000000000000000000000000000000000000000000000000000000
Found Hash 0000966b2881a6a761bb86a2d33fbfb64bd8aee8e039e25faa61d88f8e880f26
hash 0000966b2881a6a761bb86a2d33fbfb64bd8aee8e039e25faa61d88f8e880f26
hash2 0000966b2881a6a761bb86a2d33fbfb64bd8aee8e039e25faa61d88f8e880f26
CreateNewBlock(): total size 1000
Running ProtoSharesMiner with 1 transactions in block (196 bytes)
CTxMemPool::accept() : accepted 28a5342be454ec319df404e539c77a5e7a278a170ede91e6de8615d4c1cc4186 (poolsz 1)
testHash 000047d1eae1ee44cff9fcd39d864d513ead35cf51ee10805de6292396a2d8c4
Hash Target 0000fff000000000000000000000000000000000000000000000000000000000
Found Hash 000047d1eae1ee44cff9fcd39d864d513ead35cf51ee10805de6292396a2d8c4
hash 000047d1eae1ee44cff9fcd39d864d513ead35cf51ee10805de6292396a2d8c4
hash2 000047d1eae1ee44cff9fcd39d864d513ead35cf51ee10805de6292396a2d8c4
CreateNewBlock(): total size 1192
Running ProtoSharesMiner with 2 transactions in block (388 bytes)
testHash 0000f7eedfdeb810bf45d7a1b1d29ee1d80b2a9291053c520215e1964fa2b88e
Hash Target 0000fff000000000000000000000000000000000000000000000000000000000
Found Hash 0000f7eedfdeb810bf45d7a1b1d29ee1d80b2a9291053c520215e1964fa2b88e
hash 0000f7eedfdeb810bf45d7a1b1d29ee1d80b2a9291053c520215e1964fa2b88e
hash2 0000f7eedfdeb810bf45d7a1b1d29ee1d80b2a9291053c520215e1964fa2b88e
Well I had the same thing, but realy cant tell if those would have been found blocks without crash or not...

But I sugest you use a pool, way better the solo mining I think. (
http://bitsharestalk.org/index.php?topic=236.0 )