> I cannot ping a site (lucent.com) but i can ping www.lucent.com. Why?
> If i can't ping the domain name, does it mean that lucent.com is not
> exist. But why i can ping www.lucent.com. Is domain lucent.com exist?
> Can anybody explain to me why?
In all probability, lucent.com doesn't have an IP address associated
with it, but www.lucent.com does. Whether a domain has an IP address
and whether it has any subdomains are totally separate issues.
> Can linux support Pentium Pro Dual-Processor?
Yes.
> I know linux kernel can support pentium pro but how about dual
> processor. Is linux using both processor?
You need to compile the kernel for SMP. Uncomment the line
# SMP = 1
at the top of the kernel Makefile, then compile and install the
kernel. See the Kernel howto for details.
> If yes, how can i check wheater it is utilizing the dual processor
> or not? Any tool to check that?
It will tell you at boot time. Also, `cat /proc/cpuinfo' should tell
you.
> For sendmail question, if i set up a primary mail server as ServerA
> and secondary mail server ServerB and under the MX record ServerA has
> preference 5 and ServerB has preference 10. So if the mail to
> user1@ServerA arrive, of cource it will send to ServerA first. If
> ServerA down it will send to ServerB. So the question, will the mail
> send back to ServerA if ServerA is up back?
Yes, provided that you don't configure ServerB to deliver the mail
locally (via a `Cw' directive or /etc/sendmail.cf).
> How long the mail will queue on serverB?
It depends upon the Timeout.queuereturn settings specified in
sendmail.cf. The defaults are:
O Timeout.queuereturn=5d
O Timeout.queuereturn.normal=5d
O Timeout.queuereturn.urgent=2d
O Timeout.queuereturn.non-urgent=7d
Which setting is used depends upon any Precedence: headers in the
message.
> If , for instance it queue 5 day, what happen if after 5 days the
> serverA is still down?
The message will bounce, i.e. ServerB will send an message back to the
sender stating that the message couldn't be delivered.
-- Glynn Clements <glynn@sensei.co.uk> - To unsubscribe from this list: send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.rutgers.edu