DNS Resolution taking forever

void.pointer · 2008-08-02 20:19:36

Hi,

I noticed that everytime my Archlinux server needs to resolve a domain name, it takes about 10-15 seconds. Is there a way to figure out what is causing this? Thanks.

arew264 · 2008-08-02 20:38:00

Have you made any changes to /etc/nsswitch.conf?
What DNS servers are listed in /etc/resolv.conf?
Do you use DHCP or static addressing?
What kind of network are you on? (the internet (connected directly to a modem of some sort)? a home network? a corporate network?)

void.pointer · 2008-08-02 20:52:23

arew264 wrote:

Have you made any changes to /etc/nsswitch.conf?

Not that I know of.

arew264 wrote:

What DNS servers are listed in /etc/resolv.conf?

# Generated by dhcpcd for interface eth0
search router
nameserver 192.168.10.1

The above is familiar because the hostname of my router is "router", and its IP address is that listed above as "nameserver".

arew264 wrote:

Do you use DHCP or static addressing?

DHCP

arew264 wrote:

What kind of network are you on? (the internet (connected directly to a modem of some sort)? a home network? a corporate network?)

Network type is LAN. My linux machine connects directly to the router, and the router to the internet through a bridge. Keep in mind that I'm basically still running off of a default installation of Archlinux. I'm too used to Ubuntu setting things up for me so I'm probably missing some essential configuration. I had to setup my network manually, so perhaps I missed something.

arew264 · 2008-08-03 23:31:08

Do the other computers on your LAN resolve hosts using the router? Are they affected by this problem?
I assume that you have no IPTables firewall running on the Arch box, so that can't be it...

sam · 2008-08-04 00:12:50

Have you tried ping 192.168.10.1? The dns server might be slow. Do you only have 1 dns server? To check whether it is a configuration problem or or server problem try using on of the following free dns servers (by appending "nameserver xxx.xx.xxx.xxx"):

From opendns:
=> 208.67.222.222
=> 208.67.220.220

ScrubIT Free DNS Server IP address:

=> 67.138.54.100
=> 207.225.209.66

void.pointer · 2008-08-04 02:08:51

sam wrote:

Have you tried ping 192.168.10.1? The dns server might be slow. Do you only have 1 dns server? To check whether it is a configuration problem or or server problem try using on of the following free dns servers (by appending "nameserver xxx.xx.xxx.xxx"):
From opendns:
=> 208.67.222.222
=> 208.67.220.220
ScrubIT Free DNS Server IP address:
=> 67.138.54.100
=> 207.225.209.66

Sorry I don't understand. What do you mean run the command "nameserver 208.67.222.222", for example? Could you explain please? Thanks for your help, by the way.

fukawi2 · 2008-08-04 02:33:50

Can you install the dnsutils package (pacman -Sy dnsutils) and then post the output of:

dig www.google.com

Allan · 2008-08-04 02:53:12

Have you added your computers name to the localhost line in /etc/hosts?

sam · 2008-08-04 03:17:53

I meant delete "nameserver 192.168.10.1" in your /etc/resolve.conf and add "nameserver 208.67.222.222" or one of the ip addresses.

void.pointer · 2008-08-08 03:36:46

Sorry for having taken a while to respond guys. I appreciate everyone's help so far. I wasn't very specific before I guess, so I'll try again. I apologize for the confusion.

When I said DNS resolution was slow, the only place where I noticed this happening that I can remember is during a wget command. Take the output below for example:

[robert@server colors]$ wget http://blog.infinitered.com/entry_files/8/ir_black.vim
--2008-08-08 03:33:30--  http://blog.infinitered.com/entry_files/8/ir_black.vim
Resolving blog.infinitered.com... 209.20.65.189
Connecting to blog.infinitered.com|209.20.65.189|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 10140 (9.9K) [application/octet-stream]
Saving to: `ir_black.vim'

100%[=================================================>] 10,140      --.-K/s   in 0.05s

2008-08-08 03:33:40 (181 KB/s) - `ir_black.vim' saved [10140/10140]

Note the "Resolving blog.infinitered.com..." above. That line took about 10-15 seconds to process! Is this normal? Everything else on my network (Windows machines) resolve things fairly quickly.

fukawi2 · 2008-08-08 06:47:30

fukawi2 wrote:

Can you install the dnsutils package (pacman -Sy dnsutils) and then post the output of:
dig www.google.com

void.pointer · 2008-08-08 13:52:45

fukawi2 wrote:

fukawi2 wrote:
Can you install the dnsutils package (pacman -Sy dnsutils) and then post the output of:
dig www.google.com

Sorry Here it is:

[robert@server ~]$ sudo dig www.google.com
Password:

; <<>> DiG 9.5.0-P1 <<>> www.google.com
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 63003
;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;www.google.com.                        IN      A

;; ANSWER SECTION:
www.google.com.         603552  IN      CNAME   www.l.google.com.
www.l.google.com.       261     IN      A       64.233.167.147
www.l.google.com.       261     IN      A       64.233.167.99
www.l.google.com.       261     IN      A       64.233.167.104

;; Query time: 11 msec
;; SERVER: 192.168.10.1#53(192.168.10.1)
;; WHEN: Fri Aug  8 13:51:10 2008
;; MSG SIZE  rcvd: 100

fukawi2 · 2008-08-09 00:34:58

Interesting...

There should be around 19 answers for www.google.com - you go only 4

Can you try:

dig www.google.com @208.67.220.220

(btw, no need to sudo it )

Last edited by fukawi2 (2008-08-09 00:35:09)

void.pointer · 2008-08-09 00:37:14

[robert@server ~]$ dig www.google.com @208.67.220.220

; <<>> DiG 9.5.0-P1 <<>> www.google.com @208.67.220.220
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 48573
;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;www.google.com.                        IN      A

;; ANSWER SECTION:
www.google.com.         30      IN      CNAME   google.navigation.opendns.com.
google.navigation.opendns.com. 30 IN    A       208.69.32.230
google.navigation.opendns.com. 30 IN    A       208.69.32.231

;; Query time: 46 msec
;; SERVER: 208.67.220.220#53(208.67.220.220)
;; WHEN: Sat Aug  9 00:35:58 2008
;; MSG SIZE  rcvd: 104

fukawi2 · 2008-08-09 01:22:14

Hmmm.... One more

dig blog.infinitered.com
dig blog.infinitered.com @208.67.220.220

void.pointer · 2008-08-09 02:43:53

[robert@server ~]$ dig blog.infinitered.com

; <<>> DiG 9.5.0-P1 <<>> blog.infinitered.com
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 57310
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;blog.infinitered.com.          IN      A

;; ANSWER SECTION:
blog.infinitered.com.   86397   IN      A       209.20.65.189

;; Query time: 8 msec
;; SERVER: 192.168.10.1#53(192.168.10.1)
;; WHEN: Sat Aug  9 02:42:11 2008
;; MSG SIZE  rcvd: 54

[robert@server ~]$ dig blog.infinitered.com @208.67.220.220

; <<>> DiG 9.5.0-P1 <<>> blog.infinitered.com @208.67.220.220
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 64207
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;blog.infinitered.com.          IN      A

;; ANSWER SECTION:
blog.infinitered.com.   86400   IN      A       209.20.65.189

;; Query time: 113 msec
;; SERVER: 208.67.220.220#53(208.67.220.220)
;; WHEN: Sat Aug  9 02:42:27 2008
;; MSG SIZE  rcvd: 54

Arch Linux

#1 2008-08-02 20:19:36

DNS Resolution taking forever

#2 2008-08-02 20:38:00

Re: DNS Resolution taking forever

#3 2008-08-02 20:52:23

Re: DNS Resolution taking forever

#4 2008-08-03 23:31:08

Re: DNS Resolution taking forever

#5 2008-08-04 00:12:50

Re: DNS Resolution taking forever

#6 2008-08-04 02:08:51

Re: DNS Resolution taking forever

#7 2008-08-04 02:33:50

Re: DNS Resolution taking forever

#8 2008-08-04 02:53:12

Re: DNS Resolution taking forever

#9 2008-08-04 03:17:53

Re: DNS Resolution taking forever

#10 2008-08-08 03:36:46

Re: DNS Resolution taking forever

#11 2008-08-08 06:47:30

Re: DNS Resolution taking forever

#12 2008-08-08 13:52:45

Re: DNS Resolution taking forever

#13 2008-08-09 00:34:58

Re: DNS Resolution taking forever

#14 2008-08-09 00:37:14

Re: DNS Resolution taking forever

#15 2008-08-09 01:22:14

Re: DNS Resolution taking forever

#16 2008-08-09 02:43:53

Re: DNS Resolution taking forever

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