S6-FDHOLDER-TRANSFERDUMP(8)

NAME
s6-fdholder-transferdump - connect to two separate s6-fdholderd daemons and transfer the content of the first one to the second one

SYNOPSIS
s6-fdholder-transferdump [-t timeoutfrom:timeoutto] pathfrom pathto

DESCRIPTION
s6-fdholder-transferdump connects to an s6-fdholderd(8) server process listening on pathfrom and gets the whole set of file descriptors from this server, with their identifiers and (when relevant) expiration dates.

It then connects to a different instance of s6-fdholderd(8), listening on pathto, and stores the set of file descriptors in it. The set is added to the second server, which keeps the descriptors it was already holding.

Dumping the entire state of s6-fdholderd(8) requires special authorizations. Make sure the s6-fdholderd(8) instances are configured to accept dump-getting and dump-setting requests from your client. Refer to s6-fdholderd(8) for details.

A typical use case of s6-fdholder-transferdump is when the main fd-holding daemon needs to upgrade, or restart for some reason. Transferring the file descriptors into another, temporary, fd-holding daemon instance allows it to restart without losing the descriptors.

OPTIONS

-t timeoutfrom:timeoutto
    If the operations cannot be processed in timeoutfrom ( for the connection to pathfrom) or timeoutto ( for the connection to pathto) milliseconds, then fail with an error message. Communications with the servers should be near-instant, so this option is only here to protect users against programming errors (connecting to the wrong socket, for instance).

EXIT STATUS

0   Success.

1   The source server denied the operation. The meanings of the error messages are explained in s6-fdholder-error-codes(7).

2   The destination server denied the operation. The meanings of the error messages are explained in s6-fdholder-error-codes(7).

100 Wrong usage.

111 System call failed - this includes attempting to connect to a nonexistent socket, or one where no s6-fdholderd(8) daemon is listening.

SEE ALSO
s6-fdholder-daemon(8), s6-fdholder-delete(8), s6-fdholder-getdump(8), s6-fdholder-list(8), s6-fdholder-retrieve(8), s6-fdholder-setdump(8), s6-fdholder-store(8), s6-fdholderd(8)

This man page is ported from the authoritative documentation at: https://skarnet.org/software/s6/s6-fdholder-transferdump.html

AUTHORS
Laurent Bercot Alexis <flexibeast@gmail.com> (man page port)