The order of the arguments is of no importance. If target is a local directory, take care that it is an absolute pathname. You can add multiple syncs that way. The source directories may be identical or differ without problems. ```source``` is an universal parameter that must be given for every sync. All other ```sync``` parameters can differ depending on the behavior selected. Optionally you can override the default or settings values ```maxDelays``` or ```maxProcesses``` per _Sync_.
The default rsync configuration will aggregate events up to ```delay``` seconds or 1000 separate uncollapsible events, which ever happens first. Then it will spawn one Rsync with a filter of all files that changed. The filter list is transmitted to Rsync trough a pipe. A call from Lsyncd to Rsync will thus look like this:
</td><td> If absolutely needed, additional arguments can be specified as a TABLE of STRINGS(example: <tt>{ "--omit-dir-times", "--omit-link-times" }</tt>). Note that the underscore highlights this as workaround. If you need something that is not covered by the above options, please request it via a feature request on the project website. Most notably, do not add -r for recursive or -a which implies recursive, since Lsyncd will handle that by itself. Additionally do not add -R for relative, which will ruin Lsyncd <-> Rsync communication.
This configuration differs from the standard rsync configuration in that it uses ssh commands to move files or directories locally at the target host instead of deleting and transferring again. This configuration does spawn Rsync processes like default.rsync but additionally will spawn ```/usr/bin/ssh HOST mv ORIGIN DESTINATION``` commands.
If you are upgrading from 2.0.x, please notice that `settings` became a function from a variable, so you __MUST__ delete the equal sign '=' between `settings` and the `{`.
Lsyncd will call ```xargs``` on the remote host to handle multiple tasks in a single connection. Xargs options can be specified by the xargs parameter.
<table>
<tr><td> binary
</td><td> =
</td><td> FILENAME
</td><td> Lsyncd calls this binary as xargs on the remote host (default: /usr/bin/xargs)
</td></tr>
<tr><td> delimiter
</td><td> =
</td><td> DELIMITER
</td><td> delimiting character to separate filenames. By default the 0 character is used. Very old holds may need newline instead.
</td></tr>
<tr><td> _extra
</td><td> =
</td><td> STRING TABLE
</td><td> By default { '-0', 'rm -rf' }. Remove the -0 if you chose newline delimiter instead. Otherwise leave it as is.
Default.direct can be used to keep two local directories in sync with better performance than using default.rsync. Default.direct uses (just like default.rsync) rsync on startup to initially synchronize the target directory with the source directory. However, during normal operation default.direct uses /bin/cp, /bin/rm and /bin/mv to keep the synchronization. All parameters are just like default.rsync.
* Generally if any segment of the pathname (see below Layer 3) of an event matches the text, it is excluded. E.g. the file "/bin/foo/bar" matches the rule "foo".
* If the rule starts with a slash, it will only be matched at the beginning of the pathname
* If the rule ends with a slash, it will only be matched at the end of a pathname
* ? matches any character that is not a slash.
* ```*``` matches zero or more characters that are not a slash
* ```**``` matches zero or more characters, this can be slashes.
By default Lsyncd will delete files on the target that are not present at the source since this is a fundamental part of the idea of keeping the target in sync with the source. However, many users requested exceptions for this, for various reasons, so all default implementations take ```delete``` as an additional parameter.
This example will open 2 ssh connections for port forwarding and load balance 4 parallel rsync
processes in a round roubin fashion.
### Workflow in Poolmodel
When a sync with a tunnel parameter is started, all events are queued until the tunnel reaches the
`UP` state, which is when one successful tunnel process exists for at least `readyDelay` seconds.
Dead tunnel processes are automatically restarted. When the tunnel process count drops to 0, tunnel falls back to the
`CONNECTING` state. There is a `retryDelay` seconds delay between each attempt to restart the tunnel.
Once the tunnel is UP, a full transfer is initiated. Subsequent transfers are then load balanced over multiple connections.
### Notes on Poolmode
* Pool mode only works with `rsync` backend, since there is no way to prevent multiple transfers to the same file in a relieable way, the rsync backend only supports `maxProcesses = 1` which renders pool mode useless. Since the remote side rsync daemon can prevent file trashing, the rsync backend is safe.
It is possible to trigger a full sync command from within lsync with the crontab feature. This requires that [lua-crontab](https://github.com/logiceditor-com/lua-crontab) is installed on the system. The crontab configuration accepts a list of `crontab` patterns to which a full sync will be triggered.
```lua
sync {
...
crontab = {
-- does a full sync once a day at 3:00:01
"1 0 3 * * *",
},
...
}
```
### Field destination
Each field is seperated by `" "` and can contain multiple values seperated by `,`.
