26 Jan
2011
26 Jan
'11
3:24 p.m.
On Tue, Jan 25, 2011 at 10:49 PM, Mark D. Nagel <mnagel@willingminds.com> wrote:
This can bite you in unexpected ways, too. For example, on a Cisco ASA, if you add a system-level 'icmpv6 permit' line and if this does not include ND, then you break ND responses to the ASA. This is much unlike ARP, which is unaffected by 'icmp permit' statements for IPv4. And, the default with no such lines is to permit all ICMP/ICMPv6 to the ASA. This seems so obvious in retrospect, but at the time was a bit of a head-scratcher.
ARP is a seperate protocol supporting IPv4 ... For IPv6 ND is done using ICMPv6 messages. A bit confusing transitioning from IPv4/ARP for sure.
Mark