Topic: dns problem with SME 5.6

[Joel]

Hi
I just remark a dns problem with sme-server release 5.6 configured in server/gateway mode
I use it behind a firewall  (adsl speedtouch ethernet) .
For most of domains , it works fine but for some others (e.g java.sun.com or sun.com) i  cannot reach them .
for these urls ping is possible from sme but seems slow.
ping from worstations on my internal network to thes urls are not possible.
(i had not this problem on release 5.5 with rtc modem)
Thanks for your help.

[John Willby]

Hi

Just out of interest - can you get to the mitel.com site (www.mitel.com).

I also have a strange DNS problem which prevents me from getting to sun.com as well.

I have tested things with my DNS provider Zone Edit and also with the registrar of my domain as well.

BTW for testing DNS you will get a lot further with commands like dig or nslookup.

Try

dig sun.com ns

and then do a

/usr/sbin/traceroute [sun name server]

See what results you get.

Another thing to try is:

dig www.sun.com a

Hope this helps you. I am still no closer to working out my problem. I don't know if its a server setting that is the problem or if its somewhere out there on the internet.

There have been a lot of DOS attacks going down recently. Spamcop have been having real problems recently with it.

John

[joel]

Hi
first at all
you are right the same problem occurs with www.mitel.com .
a ping from sme-server fails  but
the command dig www.mitel.com succeed and gives me the address 216.191.234.137 .
a ping to this IP address fails .
maybe this server is down, it  doesn't seem to be a related dns problem.
If a try the same operation with www.java.sun.com
dig succeeds and gives me the IP address 192.18.97.39.
A ping to this IP address succeeds (from sme and intranet)
A ping to www.java.sun.com succeeds from sme (seems to be slow)
and fails from intranet.
In this case problem seems to be directly  linked to dns management .
If i bypass the SME server  (connect directly behind the adsl modem) problem doesn't occur .


Joel

[John Willby]

Hi

You problem seems different to mine. If I do a dig on these sites then I get a time out and ping does nothing unsuprisingly!

Oh well back to the head scratching. Maybe I'll connect a workstation straight to the modem and bypass the server and see if that resolves the problem. At least them I will be able to confirm if it is a server setup problem.

John

[Kelvin]

Hi guys,

Sorry I don't have a real answer for you.

Back with SME 5.1.2, I had issues with bind in that it would not resolve certain domain names. I had a number of others in the forums test the address for me and true enough those using 5.1.2 had trouble getting to the address. Setting workstation's DNS to a W2K server or a direct connection of through a simple router box all works, just not through SME 5.1.2.

In the end, I upgraded bind in 5.1.2 to the version used by SME 5.6 and that solved the problems with 5.1.2.

Perhaps you should explore the possibility of upgrading bind as well ? Or, you could try and set SME to use your ISP's DNS servers as the master DNS instead.

Kelvin

[John Willby]

Hi

Thank you that helps me.

What you say is exactly what several others have said.

Trouble is nobody tells me how to do it and I can't find a site that has the manual on it that will resolve  

I'm still fairly inexperienced in a lot of areas.

I have to confess I don't know how to find out what version of bind I have from the command promt.

I also don't know how to check which DNS servers my box is using as the master or how to change it.

I thought editing /etc/resolv.conf and putting my ISP DNS server in there would do it but I never got any resolving at all when I did that.

John

[Kelvin]

Hi John,

>how to find out what version of bind I have

rpm -q bind

>which DNS servers my box is using as the master or how to change it.

Default, SME queries the root DNS servers to resolve names.

To set a specific master DNS, login as admin (instead of root) using the same password as root. Select Configure This Server and go through the configuration screens until you get to the screen that allows you to set the master DNS servers.

Kelvin