Administrator’s Command Line Guide
Table Of Contents
- Introduction
- Accessing Acronis Storage Clusters via iSCSI
- Preparing to Work with Acronis Storage iSCSI Targets
- Creating and Running Acronis Storage iSCSI Targets
- Listing Acronis Storage iSCSI Targets
- Transferring Acronis Storage iSCSI Targets Between Acronis Storage Nodes
- Stopping Acronis Storage iSCSI Targets
- Deleting Acronis Storage iSCSI Targets
- Configuring Multipath I/O for Acronis Storage iSCSI Targets
- Managing CHAP Accounts for Acronis Storage iSCSI Targets
- Managing LUN Snapshots
- Accessing Acronis Storage Clusters via S3 Protocol
- Monitoring Acronis Storage Clusters
- Managing Cluster Security
- Maximizing Cluster Performance
6.2. Checking Data Flushing
• -s vstorage1.example.com is the hostname of the computer where the vstorage-hwflush-check server is run-
ning.
• -d /vstorage/stor1-ssd/test defines the directory to use for testing data flushing. During its execution,
the client creates a file in this directory and writes data blocks to it.
• -t 50 sets the number of threads for the client to write data to disk. Each thread has its own file and
counter. You can increase the number of threads (max. 200) to test your system in more stressful
conditions. You can also specify other options when running the client. For more information on
available options, see the vstorage-hwflush-check man page.
3. Wait for 10-15 seconds or more and power off the computer where the client is running, and then turn
it on again.
Note: The Reset button does not turn off the power so you need to press the Power button or
pull out the power cord to switch off the computer.
4. Restart the client by executing the same command you used to run it for the first time:
# vstorage-hwflush-check -s vstorage1.example.com -d /vstorage/stor1-ssd/test -t 50
Once launched, the client reads all written data, determines the version of data on the disk, and then restarts
the test from the last valid counter. It then sends this valid counter to the server, and the server compares it
with the latest counter it has. You may see output like:
id<N>:<counter_on_disk> -> <counter_on_server>
which means one of the following:
• If the counter on disk is lower than the counter on server, it means that the storage device has failed to
flush the data to disk. Avoid using this storage device in production—especially for CS or journals—as
you risk losing data.
• If the counter on disk is higher than the counter on server, it means that the storage device has flushed
the data to disk but the client has failed to report it to the server. The network may be too slow or the
storage device may be too fast for the set number of load threads so you may consider increasing it. This
storage device can be used in production.
• If both counters are equal, it means the storage device has flushed the data to disk and the client has
reported it to the server. This storage device can be used in production.
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