In a recent note, David Andrews said:
> Date: Tue, 17 May 2005 11:43:01 -0400
>
> On Mon, 16 May 2005 07:22:17 -0500, Mikael Wargh <[log in to unmask]>
> wrote:
>
> >I'm trying to automate heartbeat to one of our SMTP-servers. ICMP echo is
> >not allowed.
>
> A month ago (over on linux-390) I pointed out that servers that don't
> implement ping are broken. Per RFC1122:
>
> "Every host MUST implement an ICMP Echo server
> function that receives Echo Requests and sends
> corresponding Echo Replies"
>
Yes, but on the client side, ICMP is considered a low-level protocol,
generally not made available to non-provileged processes. For example,
on Solaris:
[EMAIL PROTECTED]:135$ ls -al `whence ping`
-r-sr-xr-x 1 root bin 48028 Jan 5 2000 /usr/sbin/ping
And, from RFC 1122:
* Active probes such as "pinging" (i.e., using an ICMP
Echo Request/Reply exchange) are expensive and scale
poorly. In particular, hosts MUST NOT actively check
the status of a first-hop gateway by simply pinging the
gateway continuously.
-- gil
--
StorageTek
INFORMATION made POWERFUL
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO
Search the archives at http://bama.ua.edu/archives/ibm-main.html
