NETMASK(1) Debian Linux NETMASK(1) NAME netmask - a netmask generation and conversion program SYNOPSIS netmask [ options ] spec [ spec ... ] DESCRIPTION This program accepts and produces a variety of common network address and netmask formats. Not only can it convert address and netmask notations, but it will optimize the masks to generate the smallest list of rules. This is very handy if you've ever configured a firewall or router and some nasty network administrator before you decided that base 10 numbers were good places to start and end groups of machines. OPTIONS -h, --help Print a summary of the options -v, --version Print the version number -d, --debug Print status/progress information -s, --standard Output address/netmask pairs -c, --cidr Output CIDR format address lists -i, --cisco Output Cisco style address lists -r, --range Output ip address ranges -x, --hex Output address/netmask pairs in hex -o, --octal Output address/netmask pairs in octal -b, --binary Output address/netmask pairs in binary -n, --nodns Disable DNS lookups for addresses DEFINITIONS A spec is an address specification, it can look like: address One address. address1:address2 All addresses from address1 to address2. address1:+address2 All addresses from address1 to address1+address2. address/mask A group starting at address spanning mask. An address is an internet network address, it can look like: ftp.gnu.org An internet hostname. 209.81.8.252 A standard dotted quad internet address notation. 100 A decimal number (100 in this case). 0100 An octal number preceded by "0" (64 in this case). 0x100 A hexadecimal number preceded by "0x" (256 in this case). A mask is a network mask, it can look like: 255.255.224.0 A dotted quad netmask (netmask will complain if it is not a valid netmask). 0.0.31.255 A Cisco style inverse netmask (preceded by a tilde (~) character). 8 The number of bits set to one from the left (CIDR notation). 010 The number of bits set to one from the left in octal. 0x10 The number of bits set to one from the left in hexadecimal. AUTHOR netmask was written by Robert Stone. Some algorithm design and optimiza- tion was provided by Tom Lear. This manual page was written by Robert Stone. BUGS Let me know if you find any. This man page is a bit more simplistic than I'd like, but I've forgotten most of the groff I once knew. SEE ALSO ipchains(1), ipfwadm(8), netstat(8), route(8), routed(8), gated(8), tcpd(8) Debian Project 15 May 1999 NETMASK(1)
NAME | SYNOPSIS | DESCRIPTION | OPTIONS | DEFINITIONS | AUTHOR | BUGS | SEE ALSO
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