netdumpd.8

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.Dd March 5, 2018
.Dt NETDUMPD 8
.Os
.Sh NAME
.Nm netdumpd
.Nd receive kernel core dumps over the network
.Sh SYNOPSIS
.Nm
.Op Fl a Ar addr
.Op Fl D
.Op Fl d Ar dumpdir
.Op Fl i Ar postscript
.Op Fl P Ar pidfile
.Op Fl p Ar path
.Sh DESCRIPTION
The
.Nm
utility listens on a UDP socket for incoming connections from a
.Fx
kernel core dumping over the network.
It effectively acts as a write-only TFTP server.
.Pp
The following options are available:
.Bl -tag -width indent
.It Fl a
Bind the daemon to the given address
.Dq Pa addr .
.It Fl D
Run the utility in debugging mode.
The daemon version is not entered while the output is printed entirely on the
console.
.It Fl d
Save the core dumps to the specified
.Dq Pa dumpdir
directory.
The default directory is
.Pa /var/crash .
.Pp
Clients may optionally specify a relative directory path when initiating a
netdump.
This path is appended to
.Dq Pa dumpdir
to obtain a directory in which to save the core dump.
The relative path may not contain ".." components.
Additionally, no symbolic link in the path may contain ".." components.
.It Fl i
Execute the script
.Dq Pa script
after each dump received.
The script accepts the following strings as parameters: a reason for
invocation, the client address, the client hostname, the info file name and the
core dump file name.
The script is executed from the
.Dq Pa dumpdir
directory.
.It Fl P
Specify an alternative file in which to store the process ID.
The default is
.Pa /var/run/netdumpd.pid .
.It Fl p
A directory path relative to
.Dq Pa dumpdir
in which to save core dumps for clients that do not specify a relative path.
Core dumps from clients that specify an invalid directory path are saved in the
default directory.
.El
.Sh SECURITY
The
.Nm
utility does not perform any authentication of clients and should therefore
be configured to listen only to trusted networks.
.Nm
can be made to write an arbitrary amount of client data to a locally-mounted
filesystem.
.Sh EXAMPLES
Run
.Nm
in the current directory, without requiring any special privileges:
.Pp
.Dl $ netdumpd -D -d Li . -P ./netdumpd.pid
.Sh SEE ALSO
.Xr netdump 4 ,
.Xr dumpon 8
.Sh HISTORY
The
.Nm
utility appeared in
.Fx 12.0 .