Re: nethack.alt.org down again???

On Feb 22, 10:39 pm, chuckcar <ch...@xxxxxxx> wrote:
The *only* time I have seen a server not responding to a
ping when it was (supposed to be) up was when a shoddy nntp server
started blocking pings (or the firewall before it as you say) and
telnets to hide their poor up-time. Yottanews if you care - *do* *not*
give them money!

Not accurate.

Many/most corporate firewalls block most/all ICMP packets, including
ping. I don't necessarily agree with this behavior, although it is
extremely commonplace.

Try, for instance to ping:
* microsoft.com (Big OS company.)
* ibm.com (Big company, runs a lot of Linux and AIX.)
* ca.com (Big software company.)
* redhat.com (OS company, presumably runs Linux and still blocks
ICMP.)

In fact, of the first 5 addreses I tried, just to check, only one
responded, which was Linux.com. And I happen to know the admins there,
and they're anal about being textbook network friendly, such as
responding to ICMP packets. Most people that run large sites don't
share this philosophy. Even ones that do will drop ICMP packets on a
whim if needed to accommodate a burst of TCP traffic.

That said, I've always responded to ICMP requests at alt.org, and see
no reason to stop that behavior anytime soon. I actually graph my
pings to the US west coast, US east coast, and the UK over time.

* http://alt.org/cacti/graph.php?local_graph_id=11&rra_id=all

There's actually an odd case of the reverse that happened on NAO
during the past few days, due to the nature of the hardware failure. A
disk drive disappeared, resulting in a running, but increasingly
hobbled, OS. Ping responded consistently until I finally shut down the
box, as the kernel had its faculties around enough to do that, but
every other port connect attempt resulted in an inability to launch
the appropriate service, thus the odd behavior of a connection,
followed by an immediate disconnect.

-drew


.

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