Ping! Ping! Ping!

[Kenny]

Hi

Can somebody educate me a little on how I interpret the fact that ping
works perfectly, expect when I try to ping my ISP's mail server for my
email accounts. This came to light when I wrote a vb program to ping
my sites and email accounts on a scheduler to give me warning of any
site/email breakdowns (I have had quite a few).

Everything worked fine, except my mailhost.xyz.com ping. The IP seems
to be perfectly active for Outlook Express. I don't have a problem
retrieving emails - but my VB ping doesn't work, and if I try to ping
directly from the command line, it times out. All other IP's, local
and remote seem fine, both from the command line and my vb program.

Q. What can cause command line ping to not work on a specific IP
address, which seems to work Ok with all other applications.

Have done the usual, disabled XP firewall and zone alarm. Can't fathom
it though. Is it possible that my ISP's mail server does not respond
to ICMP, and would that give me the 'timeout' message?

Many thanks in advance

Kenny

 

[Chuck]

Hi

Can somebody educate me a little on how I interpret the fact that ping
works perfectly, expect when I try to ping my ISP's mail server for my
email accounts. This came to light when I wrote a vb program to ping
my sites and email accounts on a scheduler to give me warning of any
site/email breakdowns (I have had quite a few).

Everything worked fine, except my *munged* ping. The IP seems
to be perfectly active for Outlook Express. I don't have a problem
retrieving emails - but my VB ping doesn't work, and if I try to ping
directly from the command line, it times out. All other IP's, local
and remote seem fine, both from the command line and my vb program.

Q. What can cause command line ping to not work on a specific IP
address, which seems to work Ok with all other applications.

Have done the usual, disabled XP firewall and zone alarm. Can't fathom
it though. Is it possible that my ISP's mail server does not respond
to ICMP, and would that give me the 'timeout' message?

Many thanks in advance

Kenny

Kenny,

It's very possible that your ISP has the email server block pings. Many public
servers, or the routers protecting them, drop pings for security or traffic
control.

Maybe you need to be more imaginative in your pinging, maybe try pinging another
target in the xyz DOT com address space.

I get "mailhost DOT xyz DOT com not found..." when I try to ping it. Is that
the return you're getting? I can ping "mailhost DOT com" successfully though.

Cheers,
Chuck

 

[Steve Winograd [MVP]]

Hi

Can somebody educate me a little on how I interpret the fact that ping
works perfectly, expect when I try to ping my ISP's mail server for my
email accounts. This came to light when I wrote a vb program to ping
my sites and email accounts on a scheduler to give me warning of any
site/email breakdowns (I have had quite a few).

Everything worked fine, except my mailhost.xyz.com ping. The IP seems
to be perfectly active for Outlook Express. I don't have a problem
retrieving emails - but my VB ping doesn't work, and if I try to ping
directly from the command line, it times out. All other IP's, local
and remote seem fine, both from the command line and my vb program.

Q. What can cause command line ping to not work on a specific IP
address, which seems to work Ok with all other applications.

Have done the usual, disabled XP firewall and zone alarm. Can't fathom
it though. Is it possible that my ISP's mail server does not respond
to ICMP, and would that give me the 'timeout' message?

Many thanks in advance

Kenny

Your ISP's mail server is probably programmed to ignore pings. That's
a common security measure, because an attacker can bring down a server
by sending it huge numbers of pings that it has to reply to.
--
Best Wishes,
Steve Winograd, MS-MVP (Windows Networking)

Please post any reply as a follow-up message in the news group
for everyone to see. I'm sorry, but I don't answer questions
addressed directly to me in E-mail or news groups.

Microsoft Most Valuable Professional Program
http://mvp.support.microsoft.com

 

[Kenny]

Chuck, Steve - Thank you very much for clarifying that
Kenny