.TH mfstopology.cfg "5" "October 2020" "MooseFS 3.0.115-1" "This is part of MooseFS"
.SH NAME
mfstopology.cfg \- MooseFS network topology definitions
.SH DESCRIPTION
The file \fBmfstopology.cfg\fP assigns IP addresses to
network locations. This file is optional. If your
network is very small (i.e. has just one switch) or
network topology is not necessary
then leave this file empty.
.SH SYNTAX
.PP
Syntax is:
.TP
\fIIP_ADDRESSES\fP \fILOCATION_PATH\fP
.PP
Lines starting with \fB#\fP character are ignored as comments.
.PP
\fIIP_ADDRESS\fP can be specified in several forms:
.PP
.nf
.ta +2i
\fB*\fP	all addresses
\fBn.n.n.n\fP	single IP address
\fBn.n.n.n/b\fP	IP class specified by network address and bits number
\fBn.n.n.n/m.m.m.m\fP	IP class specified by network address and mask
\fBf.f.f.f-t.t.t.t\fP	IP range specified by from-to addresses (inclusive)
.fi
.PP
\fILOCATION_PATH\fP can be specified as a sequence of words separated by vertical bars.
.SH NOTES
If one IP belongs to more than one definition then the last definition is used.
.PP
Distance between IP numbers is defined as follows: \fB0\fP when IP numbers are the same,
\fB1\fP when IP numbers are different, but paths specified by these numbers are the same. In case of different
paths distance is defined as one plus maximum number of elements from both paths after 
common starting part.
.PP
Distances are used to sort chunkservers during read and write operations.
They are also used by goal chunks replications if you enable \fBREPLICATIONS_RESPECT_TOPOLOGY\fP (see \fBmfsmaster.cfg\fP\|(5)).
New chunks are created randomly (without using topology information).
Rebalance routines may take distances into account (see \fBCHUNKS_UNIQUE_MODE\fP in \fBmfsmaster.cfg\fP\|(5)).
.SH EXAMPLES
192.168.1.0/24                US|CHICAGO|WTOWER|R1A
.PP
192.168.2.0-192.168.2.255     PL|WARSAW|GROCHOWSKA|R154
.PP
192.168.3.0/255.255.255.0     123
.PP
192.168.1.1                   A|B|C
.SH DISTANCE EXAMPLES
Distances calculated for two different IP numbers mapped to given location paths:
.PP
d('US','DE') = 2
.PP
d('US','') = 2
.PP
d('US|PHOENIX|AT&T|RACK1','US|PHOENIX|AT&T|RACK2') = 2
.PP
d('US|PHOENIX|AT&T|RACK1','US|PHOENIX|ATM|RACK7') = 3
.PP
d('US|PHOENIX|AT&T|RACK1','US|CHICAGO|AT&T|RACK2') = 4
.PP
d('US|PHOENIX|AT&T|RACK1','US|ATM') = 4
.PP
d('US|PHOENIX|AT&T|RACK1','DE|BERLIN|ATM|RACK175') = 5
.SH COPYRIGHT
Copyright (C) 2020 Jakub Kruszona-Zawadzki, Core Technology Sp. z o.o.

This file is part of MooseFS.

MooseFS is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, version 2 (only).

MooseFS is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with MooseFS; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02111-1301, USA
or visit http://www.gnu.org/licenses/gpl-2.0.html
.SH "SEE ALSO"
.BR mfsmaster (8),
.BR mfsmaster.cfg (5)