Examples of async commands and output
Examples of common Sync use cases and a description of async output.
Async command examples
- Continuous synchronization of a daily archive of large files on a Windows computer to Linux
computer, preserving Windows ACLs, run as an async pull on the Linux
computer:
$ async -L /sync/logs -N backup -d /sync/backup -r alligator@everglades.company.com:"C:\data\" -i /.ssh/lion_private_key -K pull --remote-scan-interval=4h --preserve-acls=metafile --remote-preserve-acles=metafile -C --exclude-dirs-older-than=1w0d0h0m0s
Details:
- Logs are stored on the Linux computer in the specified location.
- The user, lion, authenticates with an SSH key by using the
-i
option. - Because the files in the backup are large,
remote-scan-interval
is used to scan the Windows computer every 4 hours, which force an extra scan in case any notifications are missed. - To preserve Windows ACLs in the backup, both
preserve-acls=metafile
andremote-preserve-acls=metafile
must be specified. - Since the archive directory creates a new directory for each day, use
exclude-dirs-older-than=1w0d0h0m0s
to avoid scanning directories that are no longer changing (older than a week).
- High-performance push synchronization of many (10,000s) of small files (<10 KB) between
Windows
computers:
> async -L c:/logs:200 -q -N small-files -c none --pending-max=10000 --preserve-acls=native --transfer-threads=4 -R c:/logs:200 -d c:/data/ -r bobcat@192.168.4.24:"C:\data\" -K push -l 500m
Details:
- Specifying the logging locations (
-L
and-R
) is optional. Adding:200
to the end of the log directory value allows the logs to reach 200 MB before being rotated. - If the connection is secure, disabling encryption by using
-c none
might boost performance. - Increase the number of pending files from the default of 2000 using
--pending-max=10000
. - The
--preserve-acls=native
option preserves Windows ACLs. - Using more FASP threads to move the data can improve performance, set with
--transfer-threads=4
. The number of threads must not exceed the number of CPU cores (the lower value of the client and server computers). - The user must enter the password at the prompt because it is not provided in the command. Use SSH keys for authentication, even when it is not required.
- Specifying the logging locations (
- Noncontinuous bidirectional synchronization of directories that contains a mix of large and
small files in which small files are synchronized by using one thread and large files use another,
run on a Linux computer to a macOS
computer:
$ async -L /sync/logs -q -N sync-2017-01-01 -images --user=gazelle@company.com --host=10.4.25.10 -r Library/daimages -i /lion/.ssh/lion_private_key -R Library/sync/logs --transfer-threads=2:100000 -K bidi
Details:
- Logs are saved in the specified locations on both computers.
- The user authenticates with an SSH key by using the
-i
option. - The user and host are specified as separate options, rather than as part of the destination
folder, so that the username with an @ can be used (@ is reserved in an
-r
argument for specifying the host). - The async session uses two threads, one for files larger than 100 KB and one for files less than
or equal to 100 KB, specified with the
--transfer-threads
option.
- Noncontinuous push synchronization through reverse IBM Aspera Proxy:
$ async -N pushproxy -images -r lion@10.0.0.1:/daimages --proxy=dnats://gazelle:password@10.0.0.4 -K push
Details:
- The transfer username on the destination (10.0.0.1) is lion, the Proxy IP address is 10.0.0.4, and the Proxy username is gazelle.
- The Proxy URL option must include the Proxy user's password.
Async output example
When async is run in interactive mode, the status of each file in the synchronized directory is displayed in a list similar to the following output:
/file1 SYNCHRONIZED
/file2 SYNCHRONIZED(exs)
/file3 SYNCHRONIZED(skp)
/file4 SYNCHRONIZED(del)
The status might be one of the following options:
SYNCHRONIZED
: file transferredSYNCHRONIZED(skp)
: File skipped.SYNCHRONIZED(del)
: File deleted.SYNCHRONIZED(ddp)
: Dedup (duplicate files present).SYNCHRONIZED(exs)
: File exists.SYNCHRONIZED(mov)
: File changed (renamed, moved, or different attributes).