Wednesday, March 30, 2011


In both Linux and the BSD variants, the default behavior of the ICMP echo-based ping command is to enter an infinite loop, sending a probe once per second.  This results in output something like:

ubuntu:~> ping
PING ( 56(84) bytes of data.
64 bytes from icmp_req=1 ttl=52 time=35.9 ms
64 bytes from icmp_req=2 ttl=52 time=37.3 ms
64 bytes from icmp_req=3 ttl=52 time=36.2 ms
64 bytes from icmp_req=4 ttl=52 time=37.0 ms
64 bytes from icmp_req=5 ttl=52 time=36.4 ms
--- ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4004ms
rtt min/avg/max/mdev = 35.936/36.594/37.308/0.548 ms

In Solaris, on the other hand, the default output of the same command has always been to print '<machine> is alive', or 'no answer from <machine>' after a timeout.  Per the Solaris ping manual page, the Linux/BSD behavior is known as statistics mode, and has to be enabled by running ping with the -s flag.

Now, it seems that an easter egg has been added to the Solaris 11/Express ping program at build 33, remaining in later builds.  If you set the shell environment variable MACHINE_THAT_GOES_PING (I'm not joking!) to any non-null value, then the default ping behavior changes to statistics mode.  I've confirmed this as being the case on my b127 Solaris Express host.

Thanks to John Beck for the tip!

Tuesday, March 22, 2011

Thought for the (last) decade?

Just found a wonderful quote from the original, July 1974, Communications of the ACM paper on UNIX written by DMR and Ken. They say:

"Perhaps the most important achievement of UNIX is to demonstrate that a powerful operating system for interactive use need not be expensive either in equipment or in human effort"

This is perhaps something that SCO should have considered over a decade ago when they first decided to pursue Linux because (they felt) it was created far too quickly to have been done without stealing (what they believed was their) UNIX IP.