nanog mailing list archives
Re: Wake on LAN in the enterprise
From: Daniel Hagerty <hag () linnaean org>
Date: 13 Dec 2010 12:47:17 -0500
Owen DeLong <owen () delong com> writes:
WOL is unfortunately terribly deficient in that the spec. never = envisioned the possibility of a need for wake on WAN. Bottom line, it's a non-routeable layer 2 protocol. Your choices boil = down to the helper address nightmare you describe or proxy servers on every subnet.
WoL works just fine over routed networks; the magic packet format doesn't preclude it. I send WoL over routed networks several times a day. The only gotcha is that you need some kind of arrangement for either directed broadcast, or hardcode ndp/arp entries. Perl code snippet below: my $wolhost = "wolhost.example.com"; my $wolhost_mac = "de:ad:be:ef:ca:fe"; my $mac = $wolhost_mac; $mac =~ s/[: ]//g; # Use socat to build a wakeonlan packet inside a udp6 datagram. my $packed_bcast = pack("H12", "f" x 12); my $packed_mac = pack("H12", $mac); my $dgram = $packed_bcast . ( $packed_mac x 16); # 9 is the discard port. For whatever reason, the wrong thing # happens when the port is referenced by name, despite having the # name in /etc/services. open(SOCAT, "|-", (qw(socat -u STDIN), "UDP6-DATAGRAM:$wolhost:9")) || die "popen: $!"; print SOCAT $dgram || die "print: $!"; close(SOCAT);
Current thread:
- Wake on LAN in the enterprise Berry Mobley (Dec 13)
- <Possible follow-ups>
- Re: Wake on LAN in the enterprise Owen DeLong (Dec 13)
- Re: Wake on LAN in the enterprise Jack Bates (Dec 13)
- Message not available
- Re: Wake on LAN in the enterprise Jack Bates (Dec 13)
- Message not available
- Message not available
- Re: Wake on LAN in the enterprise Atticus (Dec 13)
- Re: Wake on LAN in the enterprise Jack Bates (Dec 13)
- Re: Wake on LAN in the enterprise Joel Jaeggli (Dec 23)