Re: The DF Bit Playground (Identifying Sun Solaris & OpenBSD OSs)

[Aaron Campbell <aaron () MONKEY ORG>]

On Tue, 12 Sep 2000, Ofir Arkin wrote:

> The tcpdump trace below illustrates the reply an OpenBSD 2.7 box produced
> for an ICMP Echo Request.

[snip]

> [root@godfather bin]# ./sing -echo Host_Address
> SINGing to www.openbsd.org (IP_Address): 16 data bytes
> 16 bytes from IP_Address: icmp_seq=0 DF! ttl=233 TOS=0 time=367.314 ms

You're assuming that www.openbsd.org is actually running OpenBSD. It's
not. Due to bandwidth requirements and such, it's hosted by the University
of Alberta and this box is actually running SunOS.

Reviewing tcpdump output on a Linux box pinging an OpenBSD 2.8-beta box, I
see no DF bit set in the IP header.

---
Aaron Campbell (aaron () monkey org || aaron () openbsd org)