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Dell HPC NFS Storage Solution High Availability Configurations with Large Capacities
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For comparison, here is an example of a failing test with data corruption in the copied file. For
example, if the file system is exported via the NFS async operation and there is an HA service failover
during a write operation, data corruption is likely to occur.
checkstream[compute-00-10]: ------------------------------------------------
checkstream[compute-00-10]: valid data for 51087769600 bytes at offset 45548994560
checkstream[compute-00-10]:
checkstream[compute-00-10]: ------------------------------------------------
checkstream[compute-00-10]: end of file summary
checkstream[compute-00-10]: [valid data] 1488 valid extents in 273.860652 seconds
(5.43342 err/sec)
checkstream[compute-00-10]: [valid data] 93898678272/96636764160 bytes (87 GiB/90
GiB)
checkstream[compute-00-10]: [zero data] 1487 errors in 273.860652 seconds (5.42977
err/sec)
checkstream[compute-00-10]: [zero data] 2738085888/96636764160 bytes (2 GiB/90 GiB)
checkstream[compute-00-10]: read 23592960 blocks 96636764160 bytes in 273.860652
seconds (344598 KiB/sec)
checkstream[compute-00-10]: ------------------------------------------------
checkstream[compute-00-10]: encountered 1487 errors, failing
B.4. dd
dd is a Linux utility provided by the coreutils rpm distributed with RHEL 6.1. It is used to copy a file.
The file system was mounted at /mnt/xfs on the client.
To write data to the storage, the following command line was used.
# dd if=/dev/zero of=/mnt/xfs/file bs=1M count=90000
To read data from the storage, the following command line was used.
# dd if=/mnt/xfs /file of=/dev/null bs=1M