Another ipcheck / dns setup thread

welo

Well-Known Member
Nov 11, 2002
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So recently my NOC was forced to switch their whole block of IPs to new ones and reissue them (hey, it happens). I made the switch a couple weeks back (new IPs for the nameservers etc.), all sites on the box are accessible, yet ever since I still keep getting the renowned emailed error message, e.g.:

Subject: [ipcheck] Problems with dns setup on blah.domain.com

IMPORTANT: Do not ignore this email.
The hostname (blah.domain.com) resolves to xxx.xxx.xxx.4. It should resolve to xxx.xxx.xxx.52. Please be sure to correct /etc/hosts as well as the 'A' entry in zone file for the domain.

Some are all of these problems can be caused by /etc/resolv.conf being setup incorrectly. Please check this file if you believe everything else is correct.

You may be able to automaticly correct this problem by using the 'Add an A entry for your hostname' under 'Dns Functions' in your Web Host Manager
Bad grammar and misspellings in this infernal email aside, you know the drill.

The etc/resolv.conf, nameserverips, and hosts files all setup correctly, so what am I missing? I keep futilely attempting the 'Add an A entry' thing both under 'Server Setup' and 'DNS Functions' in WHM, although I notice that if I try to use:

DNS Functions > Edit Zone Templates > Standard​

...to change my expire time or whatever, the changes do not take. I'm assuming this must be due to unwritable files (which you can never find due to the forms pointing to that nonexistant /scripts2 dir). Does anyone know exactly what files are being adjusted through that 'DNS Functions' stack of options? If I could just find them I could edit them manually and hopefully chmod them so the settings will take.

Thanks :).
 

chirpy

Well-Known Member
Verifed Vendor
Jun 15, 2002
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473
Go on, have a guess
Are you sure that /etc/hosts is setup correctly? Also check that your hostname resolves (through DNS rather than /etc/hosts) to the correct IP address and also check the alternative ethernet devide as setup under WHM > Edit Setup is correctly.
 

welo

Well-Known Member
Nov 11, 2002
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156
etc/hosts looks like:

127.0.0.1 localhost
xxx.xx.xxx.52 somename.domain.com somename

The IP is correct. Is the IP for my secondary nameserver supposed to be in there also?

I have no entry for Alternate Main Ethernet Device so must assume it's using eth0. I could not connect to the box otherwise, no?

What confuses me, is where on the box could the old IP possibly be stashed so those perpetual [ipcheck] emails keep regurgitating it? It isn't being used by anything or I should be able to reach it just by punching it into my browser address bar. Pretty weird.
 

chirpy

Well-Known Member
Verifed Vendor
Jun 15, 2002
13,466
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473
Go on, have a guess
Odd. Is your main IP address the one bound to eth0 if you do:

ifconfig eth0

You should also check /etc/ips for the old IP address(es) as well as your /etc/httpd/conf/httpd.conf
 

welo

Well-Known Member
Nov 11, 2002
71
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156
chirpy said:
You should also check /etc/ips for the old IP address(es) as well as your /etc/httpd/conf/httpd.conf
Interesting. etc/httpd/conf/httpd.conf had an entry of

<VirtualHost xxx.xxx.xxx.4>
BytesLog domlogs/somename.domain.com-bytes_log
ServerName somename.domain.com
DocumentRoot /usr/local/apache/htdocs
</VirtualHost>

...using the old IP (etc/ips looks ok).

Thanks for helping me track this down. Guess I'll wait until cron daemon runs tonight and see if another email gets generated. Will post back tomorrow confirming one way or the other.

Thanks again :).
 

welo

Well-Known Member
Nov 11, 2002
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156
chirpy said:
You can actually run the script to find out:

/scripts/ipcheck
Indeed. Well regardless, I still keep getting sent those emails either way. What a strange situation. I really hope I can track this down. It ain't stopping my box from working but it sure is annoying, and I have to wonder what problems it'll cause later :(.
 

spaceman

Well-Known Member
Mar 25, 2002
513
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318
I'm also getting similar messages. I get them approximately weekly, for 1 or more of the 3 dedicated servers we're running. There is a slight difference in the error message from the original poster. Instead of saying that the server resolves to one IP address when it should resolve to another, our warnings are *always* that the IP address resolves to '' (i,e. nothing) when it should resolve to xxx.xxx.xxx.xxx, e.g.

The hostname (abc.xyz.itomic.com) resolves to . It should resolve to 111.222.333.444

Just like the original poster, the three boxes appear to be running fine. Despite the "IMPORTANT: Do not ignore this email." part of the message we're receiving, we are indeed ignoring them and without any problems, it would seem.

Am I ok to ignore these messages? Is there some specific config problem that anyone can direct me to that would specifically cause this warning that says our server(s) resolve to 'nothing'?

Thanks in anticipation!
 

ezztro

Well-Known Member
Nov 11, 2003
148
0
166
Hello,

same Prob here since 5 Days.

IMPORTANT: Do not ignore this email.
The hostname (cust01.example.com) resolves to 195.xxxxx It should resolve to 85.xxxxx. Please be sure to correct /etc/hosts as well as
the 'A' entry in zone file for the domain.

Some are all of these problems can be caused by
/etc/resolv.conf being setup incorrectly. Please check this file if you
believe everything else is correct.

2 Month ago, i have change the Server-IP from 195.xxxx to 85 xxx No Prob. But since 5 Days cpanel is sending me this Message:

/etc/hosts

# Do not remove the following line, or various programs
# that require network functionality will fail.
85.xxxx cust01.example.com cust01
127.0.0.1 localhost

/etc/resolv.conf


domain example.com
search example.com
nameserver 85.xxxx
nameserver 62.67.58.76
nameserver 81.3.18.135

Nameser 1 = Main IP from this Server.

When i use "traceroute custo1.example.com the Server returns the 85.xxxx IP.
 

welo

Well-Known Member
Nov 11, 2002
71
0
156
I never did get rid of the emailed messages. Still get them every day for approaching three months now :).
 

welo

Well-Known Member
Nov 11, 2002
71
0
156
Think I finally fixed it. Apparently the hostname account for my box was still assigned the old IP. I never woulda found it except the other day I hit:

WHM > {DNS Functions} > Edit DNS Zone > [hostname]​

...and what do you know? The old IP was still showing up in the A entry.

I don't think this fixed it on its own however, because immediatley afterward I ran /scripts/ipcheck and was still emailed the error. Then a couple of days ago the NOC rebooted my box and I had a system-wide MySQL crash, and to get it running again I used:

/scripts/mysqlup --force
/scripts/upcp --force

Since then I stopped receiving the ipcheck error emails.