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Lame Server (how to solve it)

Posted on 2010-08-27
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Last Modified: 2013-12-06

Hi
My Dns servers are  responsible of more then 10 domians.
but one of them is giving  trouble .... but dont understand how to solved it.

One of the domain is saying ( according to Dns staff )

ERROR: You have one or more lame nameservers. These are nameservers that do NOT answer authoritatively for your domain. This is bad; for example, these nameservers may never get updated. The following nameservers are lame:

(a) When i changed in primary server, secondary server gets the update
but ::: some times is little bit of late.
note : all other domains are ok.

(b) Some times its seems like this Secondary dns server forgot that its responsible for this domain,
I know that one of the reason of lame server is that the server forget that its responsible for this domain hence it takes little bit of time to update zone record by itself

but i dont understand .. how to solved the issue ..
i can reinstall the bind and try to install again .. but i am trying to see if any one has any idea to fix it ..

thanks
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Question by:fosiul01
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by:Chris Dent
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Got dig hanging around?

Run:

dig yourdomain.com +trace

Each of the name servers listed in the NS record set, both at the parent (TLD server) and the authoritative server level must respond authoritatively for that domain. You've checked they do?

Chris
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by:fosiul01
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hi thanks

this the output ..

My domain is : www.domain.com

primary name server : ns1.domain.com
secondary name server is : ns2.domain.com
(the format is same i just opt out the domain name)



;; Received 498 bytes from 193.0.14.129#53(k.root-servers.net) in 10 ms

xxx.com.      172800  IN      NS      ns1.xxxx.com.
xxx.com.      172800  IN      NS      ns2.xxxx.com.
;; Received 103 bytes from 192.5.6.30#53(a.gtld-servers.net) in 112 ms

xxx.com.      60      IN      A       xxx.200.140.xxx
xxx.com.      60      IN      NS      ns2.xxx.com.
xxx.com.      60      IN      NS      ns1.xxx.com.
;; Received 119 bytes from ip.200.142.primary  #53(ns1.xxx.com) in 5 ms



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by:fosiul01
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that is soo wired

from last 1 weeks Dns stuff was showing i go lame server

before this question is asked , it was showing i got lame server

but now , I just did another test.. it is not showing any more!!!

what was that !!!!!

from my dig output..
do you think there is any problem ???

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by:fosiul01
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see , dnsstuff is showing again , its lame server!!!!


i cant get my head in with this problem

Please give me some advise ..

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by:Chris Dent
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Test each of the servers by running:

dig xxx.com ns @ns1.xxx.com
dig xxx.com ns @ns2.xxx.com

It might be nothing more than server load you know. Remember that all these requests are UDP based, if a request times out the server will be marked as lame (according to DNS Stuff, as far as I know).

Chris
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by:Jan Springer
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Are you using views and do you have that zone in both views?
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by:fosiul01
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Ok its refused.

but problem is i really dont see why its refusing!!!

From a different Server : ( its refused)


; <<>> DiG 9.3.6-P1-RedHat-9.3.6-4.P1.el5_4.2 <<>> xxxxx.com @ns2.xxxxx.com
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: REFUSED, id: 29923
;; flags: qr rd; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;xxxxx.com.             IN      A

;; Query time: 15 msec
;; SERVER: xxxx.174.138.xxx#53(xxx.174.138.xxx)
;; WHEN: Fri Aug 27 14:30:58 2010
;; MSG SIZE  rcvd: 35



From the Server its self  ( it worked)



[root@ns2 ~]# dig xxxx.com @ns2.xxxxx.com

; <<>> DiG 9.3.6-P1-RedHat-9.3.6-4.P1.el5_4.2 <<>> xxxx.com @ns2.xxxx.com
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 54834
;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 2

;; QUESTION SECTION:
;xxxx.com.             IN      A

;; ANSWER SECTION:
xxxx.com.      60      IN      A       xxx.200.140.xxxx

;; AUTHORITY SECTION:
xxx.com.      60      IN      NS      ns1.xxx.com.
xxx.com.      60      IN      NS      ns2.xxx.com.

;; ADDITIONAL SECTION:
ns1.xxx.com.  60      IN      A       xxx.200.142.xx
ns2.xxxx.com.  60      IN      A       xxx.174.138.xxx

;; Query time: 0 msec
;; SERVER: xxx.174.138.xxx#53(xxx.174.138.xxxx)
;; WHEN: Fri Aug 27 14:35:06 2010
;; MSG SIZE  rcvd: 119



note : other doamins are fine.. only this domain ..




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by:fosiul01
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@jesper

yes i am using view :

view    "external"
{

        match-clients           { any; };
        match-destinations      { any; };

        recursion no;
       

        allow-query-cache { none; };
       
        include "/etc/named.root.hints";

     ............................
  .................................
}


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by:fosiul01
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Bellow is my named.conf file but I don't believed its anything problem with named.conf



cat named.conf
//
// Sample named.conf BIND DNS server 'named' configuration file
// for the Red Hat BIND distribution.
//
// See the BIND Administrator's Reference Manual (ARM) for details, in:
//   file:///usr/share/doc/bind-*/arm/Bv9ARM.html
// Also see the BIND Configuration GUI : /usr/bin/system-config-bind and
// its manual.
//
options
{
        // Those options should be used carefully because they disable port
        // randomization
        // query-source    port 53;
        // query-source-v6 port 53;

        // Put files that named is allowed to write in the data/ directory:
        directory "/var/named"; // the default
        dump-file               "data/cache_dump.db";
        statistics-file         "data/named_stats.txt";
        memstatistics-file      "data/named_mem_stats.txt";

        allow-transfer {"none";};
        version "Not disclosed";
        recursion no;


};
logging
{
/*      If you want to enable debugging, eg. using the 'rndc trace' command,
 *      named will try to write the 'named.run' file in the $directory (/var/named).
 *      By default, SELinux policy does not allow named to modify the /var/named directory,
 *      so put the default debug log file in data/ :
 */
        channel default_debug {
                file "data/named.run";
                severity dynamic;
        };
};
//
// All BIND 9 zones are in a "view", which allow different zones to be served
// to different types of client addresses, and for options to be set for groups
// of zones.
//
// By default, if named.conf contains no "view" clauses, all zones are in the
// "default" view, which matches all clients.
//
// If named.conf contains any "view" clause, then all zones MUST be in a view;
// so it is recommended to start off using views to avoid having to restructure
// your configuration files in the future.
//
view    "external"
{
/* This view will contain zones you want to serve only to "external" clients
 * that have addresses that are not on your directly attached LAN interface subnets:
 */
        match-clients           { any; };
        match-destinations      { any; };

        recursion no;
        // you'd probably want to deny recursion to external clients, so you don't
        // end up providing free DNS service to all takers

        allow-query-cache { none; };
        // Disable lookups for any cached data and root hints

        // all views must contain the root hints zone:
        include "/etc/named.root.hints";

        // These are your "authoritative" external zones, and would probably
        // contain entries for just your web and mail servers:

        



       
         zone "xxxxx.com" IN {
                type slave;
                file "slaves/xxxxx.com.zone";
                masters { xxx.xxx.xxx.xxx; xxx.xxx.xxx.xxx; };


                };

};

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by:Jan Springer
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Within the zone configuration on the external view, do you have:

allow-query { any; };
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by:fosiul01
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does allow-query { any; }; is mandatory ??
i never used it .. but without this options its works fine for me ..

but i will try to add this line


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by:fosiul01
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nop, still it does not allow ... its refusing ..
dig xxx.com ns @ns2.xxx.com

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by:Jan Springer
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Could you post the real domain name?  It might help with troubleshooting?
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by:Jan Springer
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And also, does named (or whatever user named is running under) have permission to the file?

Does the zone load:  grep domain.com /var/log/messages |grep NNNNNNNN

where NNNNNNNN is the serial number.
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by:fosiul01
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ok Before putting the real domain name .. let me tell you one more thing which might gives some light ,

this is a VPS server

Initially when i bought this server it was 1 ip .

example : 1.1.1.1
then I order 2nd Ip  which they created as Bonding  example : 2.2.2.2

Now.. rest of domains name server using ip 1.1.1.1  

so primary name server is : 33.33.33.33  ( which works fine always)  (This is vps server 1)
secondary name server is : 1.1.1.1  ( which works )( VPS Server 2)


Now this problematic domain  using

primary name server : 44.44.44.44 ( which works always) (vps server 3)
secondary name server : 2.2.2.2 (which does not work) vps server 2

so this problematic domain using bonding IP of vps server...

so what i am thinking is : due to this bonding ip , its giving trouble and named service cant associate with bonding IP


but when i reboot the name service , i can see it listing on ip 2.2.2.2 , so i am more confused whats the problem ...





about permission issue :

There is not any permission issue

[root@ns2 etc]# grep xxx.com /var/log/messages | grep 2010061111
Aug 26 11:07:27 localhost named[9908]: zone xxx.com/IN/external: transferred serial 2010061111
Aug 26 11:07:27 localhost named[9908]: zone xxx.com/IN/external: sending notifies (serial 2010061111)
Aug 27 13:51:25 localhost named[16213]: zone xxx.com/IN/external: loaded serial 2010061111
Aug 27 13:51:25 localhost named[16213]: zone xxx.com/IN/external: sending notifies (serial 2010061111)
Aug 27 14:04:13 localhost named[16364]: zone xxx.com/IN/external: loaded serial 2010061111
Aug 27 14:04:13 localhost named[16364]: zone xxx.com/IN/external: sending notifies (serial 2010061111)
Aug 27 14:52:43 localhost named[16646]: zone xxx.com/IN/external: loaded serial 2010061111
Aug 27 14:52:43 localhost named[16646]: zone xxxx.com/IN/external: sending notifies (serial 2010061111)
Aug 27 14:53:50 localhost named[16704]: zone xxx.com/IN/external: loaded serial 2010061111
Aug 27 14:53:50 localhost named[16704]: zone xxxx.com/IN/external: sending notifies (serial 2010061111)


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by:Jan Springer
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If you run a:

netstat -an | grep ":53"

is named running on 0.0.0.0?

Can you ping 2.2.2.2?
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by:Chris Dent
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Is that information considered sensitive?

Chris
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by:fosiul01
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I would be really great full if you can delete the domain name ..

Company would not like it publish domain name here...

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by:Jan Springer
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The problem is with the ns2 nameserver.  It is not answering as authoritative.

We need to review the named.conf and /var/log/messages files on that server.
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by:Jan Springer
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Chris -- can you remove 33542153?
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by:fosiul01
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Thanks @Chris-Dent


about listing IP

As i said, yes its listing on both IP.. 1.1.1.1 and 2.2.2.2

tcp        0      0 1.1.1.1:53            0.0.0.0:*                   LISTEN
tcp        0      0 2.2.2.2:53           0.0.0.0:*                   LISTEN
tcp        0      0 127.0.0.1:53                0.0.0.0:*                   LISTEN
udp        0      0 1.1.1.1:53            0.0.0.0:*
udp        0      0 2.2.2.2:53           0.0.0.0:*
udp        0      0 127.0.0.1:53                0.0.0.0:*
udp        0      0 0.0.0.0:5353                0.0.0.0:*
udp        0      0 :::5353                     :::*



Any domains listed on 1.1.1.1 they dont have any problem ( primary Ip)

but this domain is listed on 2.2.2.2.. and its having this problem ... ( bonding 2nd ip )


(note : right now i am 95% convinced that its the Vps server issue )

because i can remotely connect  to the server via ssh with ip 1.1.1.1
but i cant connect to remotely via ip 2.2.2.2

i cant connect via putty to address 2.2.2.2 . but after putting user name and password, its always say deny . ( so this is one issue.) and i am thinking it might be the same problem....


in /.var/log/messages what kind of log you are expecting ???

note : there is not any deny log. it can transfer zone record from primary server.


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by:Chris Dent
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> Chris -- can you remove 33542153?

Already did :)

Chris
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by:Jan Springer
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=> Chris, I saw that I was a tad bit too slow!

=> Fosiul01, I don't know.  I can ping ns2.  Is ns2 2.2.2.2?
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by:Jan Springer
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And, does each VPS run its own firewall?
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by:fosiul01
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yap you can , its open to ping
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by:fosiul01
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And, does each VPS run its own firewall? : there is only iptables  running ..

i dont know anything about what they doing on their data centre ..


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by:fosiul01
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thats another wired !!!!

try to do ssh to

ns2.domain.co.uk ( use the same domain as .com )

then try to ssh to

ns2.domain.com

ns2.domain.co.uk : it will fail ( because of Iptables ) and its running of primary ip 1.1.1.1

but ns2.domain.com : it will connect to ssh server , and its running bonding ip 2.2.2.2


but all this year i believed.. iptables works on both IP ( primary and bonding)!!!

so there is something not right about this host

is not it ??

 

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by:Jan Springer
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So, if you're running iptables, on 2.2.2.2:

       iptables --list -n |grep "dpt:53"

Is this machine allowing TCP and UDP port 53?  (It's a question that has to be asked).  

This IP answers queries for other domains, yes?

       grep domain.com /var/log/messages

on 2.2.2.2 where domain.com is the real domain name.
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by:fosiul01
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here :

1.1.1.1 and 2.2.2.2 is ip of same server

###############################
1.1.1.1 is the Primary Ip assigned to eh0
 
2.2.2.2 is the bonding ip assigned to eth0:1
#######################

Is this machine allowing TCP and UDP port 53?  (It's a question that has to be asked).      : Yes .

-A RH-Firewall-1-INPUT -p udp -m udp --dport 53 -j ACCEPT
-A RH-Firewall-1-INPUT -p tcp -m tcp --dport 53 -j ACCEPT
I can turned it off, but currently is allowing .

about this one :   grep domain.com /var/log/messages

let me go home then i will carry on with this. I am off for today from work .
Please allow me couple of hours, i will be on online




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by:Jan Springer
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Please don't take the iptables entries out -- that will totally break your DNS queries.
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by:fosiul01
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Sorry ,i would not dare to turned off Udp port 53 !!!!

I was saying about tcp port 53

tcp port 53 in turned On  because some times some dns checker complain when tcp 53 is not turned on

i found some wired  transfer log from  IP 1.1.1.1 to primary server when it should be 2.2.2.2

I will come back after few hour with /var/log/messages log



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by:fosiul01
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 bellow log when i reboot the named service from slave server

look at domain.com and domain.co.uk

domain.com : 1.1.1.1
and domain.co.u : 2.2.2.2

here, 2.2.2.2 is the eth0
and 1.1.1.1 is the eth0:1 ( bonding)

here is not any problem with domain which is related to 2.2.2.2 , but this domain is related to 1.1.1.1 and this has problem .


Aug 27 18:03:55 localhost named[17640]: zone domain.com/IN/external: loaded serial 2010061111  
Aug 27 18:03:55 localhost named[17640]: zone domain.co.uk/IN/external: loaded serial 2010021210  
Aug 27 18:03:55 localhost named[17640]: zone domain.com/IN/external: sending notifies (serial 2010061111)  
Aug 27 18:03:55 localhost named[17640]: zone domain.co.uk/IN/external: sending notifies (serial 2010021210)  
Aug 27 18:03:55 localhost named[17640]: client 1.1.1.1#43692: view external: received notify for zone 'domain.com'  
Aug 27 18:03:55 localhost named[17640]: zone domain.com/IN/external: refused notify from non-master: 1.1.1.1#43692  
Aug 27 18:03:55 localhost named[17640]: client 2.2.2.2#43692: view external: received notify for zone 'domain.co.uk'  
Aug 27 18:03:55 localhost named[17640]: zone domain.co.uk/IN/external: refused notify from non-master: 2.2.2.2#43692  <!--[if gte mso 9]>   Normal  0      false  false  false                     MicrosoftInternetExplorer4 <![endif]--><!--[if gte mso 9]>  <![endif]--><!--[if gte mso 10]><![endif]-->Aug 27 18:03:55 localhost named[17640]:zone domain.com/IN/external: loaded serial 2010061111
Aug 27 18:03:55 localhost named[17640]:zone domain.co.uk/IN/external: loaded serial 2010021210
Aug 27 18:03:55 localhost named[17640]:zone domain.com/IN/external: sending notifies (serial 2010061111)
Aug 27 18:03:55 localhost named[17640]:zone domain.co.uk/IN/external: sending notifies (serial 2010021210)
Aug 27 18:03:55 localhost named[17640]:client 1.1.1.1#43692: view external: received notify for zone 'domain.com'
Aug 27 18:03:55 localhost named[17640]:zone domain.com/IN/external: refused notify from non-master: 1.1.1.1#43692
Aug 27 18:03:55 localhost named[17640]:client 2.2.2.2#43692: view external: received notify for zone 'domain.co.uk'
Aug 27 18:03:55 localhost named[17640]:zone domain.co.uk/IN/external: refused notify from non-master: 2.2.2.2#43692




################################################
 
I reboot the named service in primary server :
   
Aug 27 18:10:43 electab1 named[17493]: zone domain.com/IN/external: loaded serial 2010061111  
Aug 27 18:10:43 electab1 named[17493]: zone domain.co.uk/IN/external: loaded serial 2010021210  
Aug 27 18:10:43 electab1 named[17493]: zone domain.co.uk/IN/external: sending notifies (serial 2010021210)  
Aug 27 18:10:43 electab1 named[17493]: zone domain.com/IN/external: sending notifies (serial 2010061111)  
  This is the log from Slave after reboot the primary server :  
   
   
   
Aug 27 18:12:16 localhost named[17640]: client 3.3.3.3#29084: view external: received notify for zone 'domain.co.uk'  
Aug 27 18:12:16 localhost named[17640]: zone domain.co.uk/IN/external: notify from 3.3.3.3#29084: zone is up to date  



Now if you look at log at primary server :
its sending notify to slave for both domain.com and domain.co.uk

now look at slave log
its only taking notify for domain.co.uk , but there is not anything about domain.com !!!



its like to me its forgetting that this server is responsible for domain.com!! [ i guess its call lame ]
that name server forget that it is responsible for its domain

but ....

if i change the serial number of primary .. it will change to secondary [ not straight way .. after couple minutes may be couple of hour it will change serial  number of slave automatically ]

hence i am confused .. whats going on ....

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Aug 27 18:03:55 localhost named[17640]:client 1.1.1.1#43692: view external: received notify for zone 'domain.com'

Aug 27 18:03:55 localhost named[17640]:zone domain.com/IN/external: refused notify from non-master: 1.1.1.1#43692

In the global named.conf above your 'options':

acl "notifies" {
       1.1.1.1;
       2.2.2.2;
};

allow-notify {notifies;};
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by:fosiul01
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Sorry for late reply. had to break my fast.

I tryed with bellow setting before ..

allow-notify { 1.1.1.1; 2.2.2.2};

but it did not helped. it used to stop taking notify from master server..

does not it same as  bellow ?


acl "notifies" {
       1.1.1.1;
       2.2.2.2;
};

allow-notify {notifies;};    




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by:Jan Springer
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It's the same except that you need a ";' after 2.2.2.2.  You may need to put the allow-notify in the zone section.  I think that the problem is that if 1.1.1.1 and 2.2.2.2 are on the same machine, the notify may be coming from and to the same IP.

If that's a copy/paste from named.conf, named should have complained about the syntax.  Please verify the syntax and that named has been restarted.
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by:fosiul01
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Hi sorry

Due to Bank holiday weakend, i was off from work!!
Came back today ..
your comments :

I think that the problem is that if 1.1.1.1 and 2.2.2.2 are on the same  machine, the notify may be coming from and to the same IP.    


yes thats what i am thinking.. that its something to do with VPS configurations.

Example : I have another vps server with different company and it has bonding as well.

i can connect to that vps server by using bonding IP.
but with this problematic vps servcer(1.1.1.1 , 2.2.2.2), i cant connect to server by using bonding

anyway... i will email to vps provider ..


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by:Jan Springer
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Actually, I believe it has to do with the notifier and the receipt of the notifies occurring with the same IP address.  I don't believe that it's VPS specific.
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by:fosiul01
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I just added notify as you said.. and this is the log which i told you before ID:33546424


Aug 31 12:51:53 localhost named[15434]: zone xxxx.com/IN/external: loaded serial 2010061111
Aug 31 12:51:53 localhost named[15434]: zone xxxxx.com/IN/external: sending notifies (serial 2010061111)
Aug 31 12:51:54 localhost named[15434]: client 22.22.22.22#28827: view external: received notify for zone 'xxxxx.com'
Aug 31 12:51:54 localhost named[15434]: zone xxxx.com/IN/external: notify from 22.22.22.22#28827: zone is up to date


Here : I changed the serial number on master server. from master server is sending notify to slave server.

but slave is not reeving

but when i am restarting the slave,   [allow-notify { 1.1.1.1; 2.2.2.2;};

since we set notify to itself, its thinking, zone is up to date!!!


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by:fosiul01
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Ok , its started the zone transfer after 10 minutes ( this was problem from before ..)

but still its show as lame server.

i dont know ....  who to blame for ..
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by:Jan Springer
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Give me a bit and I'll get back with you.
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by:Jan Springer
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Could you post a sanitized copy of ns2's named.conf?

Substitute the first two octets with "192.168"

For the domains, use 'domain1.com' through 'domainX.com' where X is a number.  Let me know which 'domain' is ns2 in the conf.  I don't need to see the inverse zones.

Thanks.
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i just emailed to vps provider

its their reply


Hi Fosiul,
 
 It seems that 22.22.22.22has become corrupted within our system, we  have now assigned 44.44.44.44 to your server. Please let us know if  you have any further questions or require us to help setup the IP on  your server.
 
 Kind regards
 
 Cloud Next



see told you!!

let me try with new IP, i need to email to my domain provider to change host record!!!

i will come back
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by:fosiul01
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it was the corrupted ip problem
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