| ascp: Transferring from the Command Line with Ascp |
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Preserve file timestamps for access and modification time. Equivalent to setting
--preserve-
modification-time
and
--preserve-access-time
(and
--preserve-creation-
time
on Windows). Timestamp support in object storage varies by provider; consult your object
storage documentation to determine which settings are supported.
On Windows, modification time may be affected when the system automatically adjusts
for Daylight Savings Time (DST). For details, see the Microsoft KB article,
support.microsoft.com/kb/129574
.
On Isilon IQ OneFS systems, access time (
atime
) is disabled by default. In this case,
atime
is the
same as
mtime
. To enable the preservation of
atime
, run the following command:
# sysctl efs.bam.atime_enabled=1
--partial-file-suffix=
suffix
Enable the use of partial files for files that are in transit, and set the suffix to add to names of partial
files. (The suffix does not include a "
.
", as for a file extension, unless explicitly specified as part
of the suffix.) This option only takes effect when set on the receiver side. When the transfer is
complete, the suffix is removed. (Default: suffix is null; use of partial files is disabled.)
--policy={high|fair|low|fixed}
Set the FASP transfer policy.
•
high
- Adjust the transfer rate to fully utilize the available bandwidth up to the maximum rate.
When congestion occurs, the transfer rate is twice as fast as a fair-policy transfer. The
high
policy requires maximum (target) and minimum transfer rates.
•
fair
- Adjust the transfer rate to fully utilize the available bandwidth up to the maximum rate.
When congestion occurs, bandwidth is shared fairly by transferring at an even rate. The
fair
policy requires maximum (target) and minimum transfer rates.
•
low
- Adjust the transfer rate to use the available bandwidth up to the maximum rate. Similar
to fair mode, but less aggressive when sharing bandwidth with other network traffic. When
congestion occurs, the transfer rate is reduced to the minimum rate until other traffic decreases.
•
fixed
- Attempt to transfer at the specified target rate, regardless of network or storage
capacity. This can decrease transfer performance and cause problems on the target storage.
Aspera discourages using the
fixed
policy except in specific contexts, such as bandwidth
testing. The
fixed
policy requires a maximum (target) rate.
If
--policy
is not set,
ascp
uses the server-side policy setting (
fair
by default). If the server
does not allow the selected policy, the transfer fails.
--precalculate-job-size
Calculate the total size before starting the transfer. The server-side
pre_calculate_job_size
setting in
aspera.conf
overrides this option.
--preserve-access-time
Preserve the source-file access timestamps at the destination. Because source access times are
updated by the transfer operation, the timestamp preserved is the one just
prior
to the transfer.
(To prevent access times at the source from being updated by the transfer operation, use the
--
preserve-source-access-time
option.)
On Isilon IQ OneFS systems, access time (
atime
) is disabled by default. In this case,
atime
is the
same as
mtime
. To enable the preservation of
atime
, run the following command:
# sysctl efs.bam.atime_enabled=1
--preserve-acls={native|metafile|none}
