...and dumped a crash dump out to disk. Exception object: 0000000084f58ba8 Exception type: System.IO.IOException Message: The process cannot access the file 'i:\blobcache\1356864981\dump.bin' because it is being used by another process. InnerException: <none> StackTrace (generated): SP IP Function 000000001E82DC50 0000064278CE14B8 mscorlib_ni!System.IO.__Error.WinIOError(Int32, System.String)+0xa0e528 000000001E82DCB0 000006427835771A mscorlib_ni!System.IO.File.Delete(System.String)+0x17a 000000001E82DD20 000006428176396B Microsoft_SharePoint_Publishing!Microsoft.SharePoint.Publishing.BlobCache.WriteIndex(Boolean)+0x52b 000000001E82DFE0 00000642824200BC Microsoft_SharePoint_Publishing!Microsoft.SharePoint.Publishing.BlobCache.WriteIndex()+0x2c 000000001E82E010 000006428241DABE Microsoft_SharePoint_Publishing!Microsoft.SharePoint.Publishing.BlobCache+<>c__DisplayClass14+<>c__DisplayClass17.<FetchItemFromWss>b__11()+0xb4e 000000001E82E340 000006428095EADF Microsoft_Office_Server_Diagnostics!Microsoft.Office.Server.Diagnostics.FirstChanceHandler.ExceptionFilter(Boolean, TryBlock, FilterBlock, CatchBlock, FinallyBlock)+0x4f It looks as though Blobcache was in contention for the ‘dump.bin’ file with something else but what that something else was is unclear. I’m not certain whether this final exception is the cause of the problem or the final sign that something went wrong. We experienced the loss of three out of the four servers currently in service and we’re pretty certain it was caused by Blobcache. The other WFEs became slow and unresponsive - they were still able to serve content but were very slow to do it. WFE04 died completely While all the servers were being unresponsive, they were timing out while trying to serve content controlled by blobcache such as images and css files. ~Cheers Jonj

I notice your blobcache is on the I:\ drive. Is that a LOCAL drive? Or a network share? Or a SAN drive? If all your servers are configured to write blogcache to a location that isn't local to the server, then contention will occur. Here's the guide to enabling disk based cache: http://office.microsoft.com/en-us/sharepointserver/HA101762841033.aspx Ensure cache location is local to the server.I trust that answers your question... Thanks C http://www.cjvandyk.com/blog

I:\ is a local drive Configuration seems to be fine - raised a call to MS about this - I'll post back when I get some more info