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NAME

cta-fst-gcd --- Garbage Collector Daemon for EOS FSTs with CTA tape back-end enabled

SYNOPSIS

cta-fst-gcd [--help] [--config config_file] [--stdout]

DESCRIPTION

cta-fst-gcd is a daemon that runs on an EOS disk server (FST), to garbage collect (evict) disk replicas which have been safely archived to tape.

The cta-fst-gcd daemon scans every single EOS disk file on the FST. A file is garbage collected if:

  • The amount of free space on the corresponding file system is considered too low.

  • The file is considered old enough to be garbage collected.

The cta-fst-gcd daemon garbage collects an EOS disk file by extracting the hexadecimal EOS file identifier (fxid) from the local disk filename and then running:

eos stagerm fxid:fxid.

OPTIONS

-h, --help

Display command options and exit.

-c, --config config_file

Set the path of the configuration file. Defaults to /etc/cta/cta-fst-gcd.conf.

-s, --stdout

Sets log output to stdout. This disables use of a log file.

CONFIGURATION

The cta-fst-gcd daemon reads its parameters from its configuration file, by default /etc/cta/cta-fst-gcd.conf.

log_file = /var/log/eos/fst/cta-fst-gcd.log

Path of the garbage collector log file.

mgm_host = HOSTNAME.2NDLEVEL.TOPLEVEL

Fully qualified host name of EOS MGM.

eos_spaces = EOS_SPACE_1 EOS_SPACE_2

Space-separated list of names of the EOS spaces to be garbage collected.

eos_space_to_min_free_bytes = EOS_SPACE_1:10000000000 EOS_SPACE_2:10000000000

Minimum number of free bytes each filesystem should have.

gc_age_secs = 7200

Minimum age of a file before it can be considered for garbage collection.

absolute_max_age_secs = 604800

Age at which a file will be considered for garbage collection, regardless of the amount of free space.

query_period_secs = 310

Delay in seconds between free space queries to the local file systems.

main_loop_period_secs = 300

Period in seconds of the main loop of the cta-fst-gcd daemon.

xrdsecssskt = /etc/eos.keytab

Path to Simple Shared Secrets keytab to authenticate with EOS MGM.

EXIT STATUS

cta-fst-gcd returns 0 on success.

FILES

/etc/cta/cta-fst-gcd.conf

Default location for the configuration file of the cta-fst-gcd daemon. This can be overriden using the --config option. See CONFIGURATION above, and /etc/cta/cta-fst-gcd.conf.example.

/var/log/eos/fst/cta-fst-gcd.log

The default log file of the cta-fst-gcd daemon. This can be changed in cta-fst-gcd.conf or disabled with the --stdout option.

SEE ALSO

CERN Tape Archive documentation https://eoscta.docs.cern.ch/

COPYRIGHT

Copyright © 2024 CERN. License GPLv3+: GNU GPL version 3 or later http://gnu.org/licenses/gpl.html. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. In applying this licence, CERN does not waive the privileges and immunities granted to it by virtue of its status as an Intergovernmental Organization or submit itself to any jurisdiction.