Data retrieval to CAPS using SeedLink plugins.


slink2caps uses the available SeedLink plugins to feed data from other sources into caps. Data can be retrieved from any sources for which a SeedLink plugins exists. The data will be converted into MiniSeed format.

Transient packets

The plugin data acquisition and the CAPS outgoing connection is not synchronized so that packets might be received by plugins but could not be forwarded to CAPS since the plugin is not allowed to send data to the server or the server is not reachable. In this case packets are in transient state and would be lost on shutdown. To prevent packet loss the plugin stores all transient packets to disk during shutdown by default. Set the parameter bufferFile to use an alternative location.


Keep in mind to remove the buffer file before plugin start to reset the data acquisition completely.

Module Configuration


slink2caps inherits global options.


Modules/plugins may require a license file. The default path to license files is @DATADIR@/licenses/ which can be overridden by global configuration of the parameter gempa.licensePath. Example:

gempa.licensePath = @CONFIGDIR@/licenses

Default: @ROOTDIR@/var/lib/slink2caps/buffer.mseed

Type: path

Path to buffer file where transient packets are stored on disk during shutdown. Transient means packets that have been received from input plugins, e.g., chain_plugin but have not been acknowledged by CAPS. Without local storage on disk those packets would be lost. During start the plugin reads the buffer file and tries to send the packets again. Please keep in mind to remove the buffer file before plugin start in case of the data acquisition should be reset.


seedlink.* Data input control


Default: @ROOTDIR@/var/lib/seedlink/seedlink.ini

Type: path

Path to Seedlink configuration file. Use the respective name if seedlink runs as an alias.

Default: seedlink

Type: string

Name of Seedlink configuration section. Use the respective name if seedlink runs as an alias.


output.* Data output control


Default: false

Type: boolean

Write miniSEED records to stdout instead of pushing them to CAPS.


Default: localhost:18003

Type: string

Data output URL [[caps|capss]://][user:pass@]host[:port]. This parameter superseds the host and port parameter of previous versions and takes precedence.

Default: localhost

Type: string

Data output host. Deprecated: Use output.address instead.


Default: 18003

Type: int

Data output port. Deprecated: Use output.address instead.


Default: 60

Unit: s

Type: int

Timeout when sending a packet. If the timeout expires the connection will be closed and re-established.


Default: 131072

Unit: bytes

Type: uint

Size (bytes) of the packet buffer


Default: 0

Unit: s

Type: int

Length of backfilling buffer. Whenever a gap is detected, records will be held in a buffer and not sent out. Records are flushed from front to back if the buffer size is exceeded.


Default: @ROOTDIR@/var/run/rs2caps/journal

Type: string

File to store stream states


Default: 10

Unit: s

Type: uint

Flush stream states to disk every n seconds


Default: 60

Unit: s

Type: uint

Wait when a sync has been forced, up to n seconds


Default: 5

Unit: s

Type: uint

Wait on shutdown to receive acknownledgement messages, up to n seconds


Default: false

Type: boolean

Log information status information e.g. max bytes buffered


Default: 10

Type: uint

Flush status every n seconds to disk

Command-Line Options


-h, --help

Show help message.

-V, --version

Show version information.

--config-file arg

Use alternative configuration file. When this option is used the loading of all stages is disabled. Only the given configuration file is parsed and used. To use another name for the configuration create a symbolic link of the application or copy it. Example: scautopick -> scautopick2.

--plugins arg

Load given plugins.

-D, --daemon

Run as daemon. This means the application will fork itself and doesn’t need to be started with &.

-f, --seedlink-config arg

Path to Seedlink configuration file. Default: @ROOTDIR@/var/lib/seedlink/seedlink.ini

-n, --section-name arg

Name of Seedlink configuration section. Default: seedlink.


--verbosity arg

Verbosity level [0..4]. 0:quiet, 1:error, 2:warning, 3:info, 4:debug.

-v, --v

Increase verbosity level (may be repeated, eg. -vv).

-q, --quiet

Quiet mode: no logging output.

--print-component arg

For each log entry print the component right after the log level. By default the component output is enabled for file output but disabled for console output.

--component arg

Limit the logging to a certain component. This option can be given more than once.

-s, --syslog

Use syslog logging backend. The output usually goes to /var/lib/messages.

-l, --lockfile arg

Path to lock file.

--console arg

Send log output to stdout.


Execute in debug mode. Equivalent to –verbosity=4 –console=1 .


Execute in trace mode. Equivalent to –verbosity=4 –console=1 –print-component=1 –print-context=1 .

--log-file arg

Use alternative log file.


-H, --host arg

Data output host. Default: localhost.

-p, --port arg

Data output port. Default: 18003.

-c, --stdout

Write records to stdout.