Gordon Messmer wrote:
Karl Larsen wrote:
This morning I started the computer and it stopped for 10 minutes
because it could not find cups. It talked about applying iptables but
had "never matched protocal" and when it finally came up Thunderbird
was broken.
...
After checking your SELinux settings, you should have checked resolution
of your hostname. To do this, start by establishing what your hostname is:
# hostname
herald.private.dragonsdawn.net
Then make sure that hostname can be resolved, either by the hosts file
or DNS:
# getent hosts `hostname `
192.168.1.6 herald.private.dragonsdawn.net
If you get an error from "getent", then you need to make sure that your
hostname can be resolved. You can do this by listing it in /etc/hosts,
or by setting up the name in DNS.
This is my suspicion for Karl's issue as well. Even though it isn't my
issue, I would like to confirm the root cause of the problem.
A final test is does ping `hostname` actually get "reply"s ?
ie: ping k5di
Even if it the hostname is pingable now, I think it would not have been
pingable at the time when Karl had the initial problem. His contents of
/etc/resolv.conf showed the comment from dhclient. I'll put down some
further possibilities that may have led to this issue {that seemed to
resolve itself}.
Since likely a DSL connection to the internet:
- Network cable faulty or partially plugged in {wired} ?
- Assuming a DSL router does the pppoe login:
- powered off
- rebooting at the inopportune moment {check the uptime of the router}
- relogging on due to inactivity timeout {check the router logs - and
that it time marks are correct time}
- failed to give out an dhcp address ?
- isp dns server down at the time the pc is trying to resolve its
hostname {instead of an instant ~"does not exist", PC's dns gets no
answer, timing out after 1 minute, then trying again a couple of
times...} {check the ISPs service status - decent ones tell you when
they have had issues} {also causes slow startup for thunderbird since it
can't resolve the mail server name}.
- the received dhcp address has a domain that does not exist {if I
set domain in my router's dhcp server as "zzz", then for eg sendmail
needs to be able to resolve `hostname`.zzz - it will timeout after 1
minute, try again, time out after the second minute, then sm-client will
also timeout - leads to a 3 minute boot delay}.
- A change to a PC setting:
- hostname changed {and not updated in /etc/hosts} ?
- firewall config change ?
- package update {less /var/log/yum.log} ?
eg: Sep 28 22:47:50 Updated: iptables-ipv6 - 1.3.8-2.1.fc7.i386
eg: Oct 11 22:54:16 Updated: dbus-glib - 0.73-3.fc7.i386
{it might help us to see the most recent 50 entries from yum.log}
- An issue in a package
- network manager, dbus, dhclient, iptables ?
- "fail to find cups and then sendmail":
- The description is poor. A better one might be "the system shows:
Starting cups ... and then sits there for some minutes. This also
occurred at the starting sendmail / sm-client ... part". It is not that
the system can't find either of these programs, but that they are taking
more than normal time to startup.
- "Thunderbird was broken"
- There was no further mention of the nature of the issue with
thunderbird. Was it delay in getting email ? Were there any error
messages ? what exactly was the issue ? Was it delay in starting
thunderbird at all ?
I have found it useful to have a pen/paper near my computer so that I
can catch any weirdness as close to the letter as possible. I also have
an old digital watch there, so that I can time {in seconds} something
that seems to be taking to long - sometimes that is enough to indicate
the type of fault to others.
I am sure there are more possibilities that can lead to the symptoms
described by Karl.
DaveT.
