Category Archives: networking

Linux HOWTO Enable Miltucast Ping (ICMP) Replies (Echo)

The 2.6 Linux kernel does not respond to multicast ICMP Echo requests by default. This is a setting in /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts Test it: # cat /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts 1 # Set it to 0 for ping replies: # echo “0” > /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts # … Continue reading

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Perl code to find an IP A in subnet B/C

my $ip = ‘’; my $block1 = ‘’; if(checkip($ip, $block1)) { print STDOUT “$ip is in $block1\n”; } else { print STDOUT “$ip is not in $block1\n”; } sub checkip() { my $ip = shift; my $block = shift; @ip1 … Continue reading

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