Is this a bug?

[Sundj]

%uname -a
FreeBSD 7.0-RELEASE FreeBSD 7.0-RELEASE #0: Sun Feb 24 19:59:52 UTC 2008 root@logan.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC i386
%ping dl_dir.qq.com
ping: cannot resolve dl_dir.qq.com: Unknown server error



[sundj@WebServer ~]$ uname -a
Linux WebServer 2.6.9-5.ELsmp #1 SMP Wed Jan 5 19:30:39 EST 2005 i686 i686 i386 GNU/Linux
[sundj@WebServer ~]$ ping dl_dir.qq.com
PING dl_dir1.qq.com (221.236.30.114) 56(84) bytes of data.
64 bytes from 221.236.30.114: icmp_seq=0 ttl=52 time=37.9 ms
64 bytes from 221.236.30.114: icmp_seq=1 ttl=52 time=37.5 ms



C:\>ping dl_dir.qq.com

Pinging dl_dir.tc.qq.com [60.28.230.162] with 32 bytes of data:

Reply from 60.28.230.162: bytes=32 time=17ms TTL=53
Reply from 60.28.230.162: bytes=32 time=17ms TTL=53


I think this is must be a bug!

[kamikaze]

What exactly is supposed to be a bug?

[Cka3o4Huk]

IIUC, Sundj's problem is DNS resolving under BSD.
Please, look man 5 resolver.

[kamikaze]

It could simply be that he isn't connected, didn't run dhclient, any of these things.

[Cka3o4Huk]

Concerning with different IP addresses of dl_dir.qq.com:
1) 221.236.30.114 - internal
2) 60.28.230.162 - external

Depends on order of DNSs in list.

[lme@]

Please create threads in the appropriate section.

Thank you!

[Vladimir]

It's impossible, that such threads appear. The template of thread is necessary.

[vivek]

Update /etc/resolv.conf file. Here is my file
cat /etc/resolv.conf
nameserver 4.2.2.1
nameserver 4.2.2.2
nameserver 4.2.2.3


Make sure firewall (PF or IPFW) is allowing access to DNS server.

[Sundj]

Please create threads in the appropriate section.

Thank you!

i'm sorry!

[Sundj]

ah ha ~:)

I think this is a bug with parse domain name.
"dl_dir.qq.com" can be parsed on Linux and windows， but couldn't on FreeBSD
I found that it will not be pasred, resolved by FreeBSD which domain name include char "_".

My English is poor, but i realy would like to talk to you ~ Can u understand me? :(

[Vladimir]

do it:
dig dl_dir.qq.com

[Sundj]

%dig dl_dir.qq.com

; <<>> DiG 9.4.2 <<>> dl_dir.qq.com
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 5417
;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;dl_dir.qq.com. IN A

;; ANSWER SECTION:
dl_dir.qq.com. 255 IN CNAME dl_dir.tc.qq.com.
dl_dir.tc.qq.com. 352 IN A 60.28.230.163
dl_dir.tc.qq.com. 352 IN A 60.28.230.164
dl_dir.tc.qq.com. 352 IN A 60.28.230.162

;; Query time: 3 msec
;; SERVER: 202.106.0.20#53(202.106.0.20)
;; WHEN: Wed Nov 19 21:46:41 2008
;; MSG SIZE rcvd: 103

%


the result

[Vladimir]

So, has you see, you don't have problem with resolving. Odds-on problem with your network. You have provided insufficient information to fix your problem.

[Sundj]

Thanks Vladimir.

I try to express myself exactly, but a little hard :( Sorry~

I havn't problem.

When I did this "ping dl_dir.qq.com" on FreeBSD, it got error "ping: cannot resolve dl_dir.qq.com: Unknown server error"
but on linux or windows havn't this error.

Because there is a "_" in "dl_dir.qq.com".

So I think that was a BUG to FreeBSD ... Can you understand me :(

[Cka3o4Huk]

riddler# uname -a
FreeBSD riddler 7.0-STABLE-200807 FreeBSD 7.0-STABLE-200807 #0: Mon Jul 14 22:45:15 UTC 2008 root@logan.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC
riddler# ping dl_dir.qq.com
PING dl_dir1.qq.com (58.211.84.131): 56 data bytes

It seems there is no bug.

[Vye]

Thanks Vladimir.

I try to express myself exactly, but a little hard :( Sorry~

I havn't problem.

When I did this "ping dl_dir.qq.com" on FreeBSD, it got error "ping: cannot resolve dl_dir.qq.com: Unknown server error"
but on linux or windows havn't this error.

Because there is a "_" in "dl_dir.qq.com".

So I think that was a BUG to FreeBSD ... Can you understand me :(

I don't think anyone is having a problem understanding what you're saying. You just have not provided any information that points to FreeBSD as the cause of your problem. Your network/NIC does not appear to be configured appropriately.

Maybe you could try using telnet to connect to a service on that domain instead of using ICMP (ping) to test the connection? It appears to be at least somewhat functional since you can do DNS queries.

Example:
[vye@nms ~]$ telnet dl_dir.qq.com 80
Trying 221.236.30.114...
Connected to dl_dir1.qq.com.
Escape character is '^]'.


If you have any firewall services running it would be to your benefit to temporarily disable them while troubleshooting.

[bsddaemon]

Interesting, I got this "bug", too, even telnet doesnt work either


bsddaemon@workstation:~% ping dl_dir.qq.com
ping: cannot resolve dl_dir.qq.com: Unknown server error


I tried with 2 other Linux servers, it works fine

I run my own FreeBSD DNS server (BIND), and I suspect it would be culprit :S

[DutchDaemon]

FreebSD 7.1-PRE with BIND 9.5.0-p2 has no problem with this (though the underscore violates an RFC, I believe).

[tbyte]

First of all '_' is not allowed symbol in a domain name according to http://tools.ietf.org/html/rfc1034 ...
So tell Your admin to fix it, because other resolvers can refuse to even try to work with it.

[DutchDaemon]

Certainly not in a domain name, no, but I think the jury's rather undecided about underscores in the hostname part of a fqdn.

[gordon@]

Certainly not in a domain name, no, but I think the jury's rather undecided about underscores in the hostname part of a fqdn.

The RFC is pretty clear actually. Underscores are reserved characters that are not supposed to be in a fqdn at all. I would suggest that the underscore in the hostname is the root of the problem. Change it to a hyphen and see if the problem goes away.

[SirDice]

Seems to work fine?


dice@williscorto:~>dig dl_dir.qq.com

; <<>> DiG 9.4.2-P1 <<>> dl_dir.qq.com
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 43864
;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 2, ADDITIONAL: 0

;; QUESTION SECTION:
;dl_dir.qq.com. IN A

;; ANSWER SECTION:
dl_dir.qq.com. 600 IN CNAME dl_dir1.qq.com.
dl_dir1.qq.com. 600 IN A 58.211.84.131
dl_dir1.qq.com. 600 IN A 221.236.30.114
dl_dir1.qq.com. 600 IN A 221.236.30.115

;; AUTHORITY SECTION:
dl_dir1.qq.com. 7200 IN NS ns-cnc1.qq.com.
dl_dir1.qq.com. 7200 IN NS ns-cnc2.qq.com.

;; Query time: 1542 msec
;; SERVER: 192.168.1.1#53(192.168.1.1)
;; WHEN: Wed Nov 19 20:48:06 2008
;; MSG SIZE rcvd: 145

dice@williscorto:~>nslookup dl_dir.qq.com
Server: 192.168.1.1
Address: 192.168.1.1#53

Non-authoritative answer:
dl_dir.qq.com canonical name = dl_dir1.qq.com.
Name: dl_dir1.qq.com
Address: 221.236.30.115
Name: dl_dir1.qq.com
Address: 58.211.84.131
Name: dl_dir1.qq.com
Address: 221.236.30.114

dice@williscorto:~>ping dl_dir.qq.com
PING dl_dir1.qq.com (221.236.30.114): 56 data bytes
64 bytes from 221.236.30.114: icmp_seq=0 ttl=48 time=383.579 ms
64 bytes from 221.236.30.114: icmp_seq=1 ttl=48 time=383.036 ms
64 bytes from 221.236.30.114: icmp_seq=2 ttl=48 time=383.383 ms
64 bytes from 221.236.30.114: icmp_seq=3 ttl=48 time=383.094 ms
^C
--- dl_dir1.qq.com ping statistics ---
4 packets transmitted, 4 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 383.036/383.273/383.579/0.220 ms
dice@williscorto:~>uname -a
FreeBSD williscorto.dicelan.home 7.1-PRERELEASE FreeBSD 7.1-PRERELEASE #0: Wed Oct 15 14:01:36 CEST 2008 root@molly.dicelan.home:/usr/obj/usr/src/sys/CORTO i386


Sundj, check your /etc/resolv.conf

[Sundj]

OK, I have checked my resolv.conf

%cat /etc/resolv.conf
nameserver 203.196.0.6
nameserver 203.196.1.6
nameserver 202.106.0.20

%ping 203.196.0.6
PING 203.196.0.6 (203.196.0.6): 56 data bytes
64 bytes from 203.196.0.6: icmp_seq=0 ttl=250 time=0.950 ms
64 bytes from 203.196.0.6: icmp_seq=1 ttl=250 time=0.667 ms
^C
--- 203.196.0.6 ping statistics ---
2 packets transmitted, 2 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 0.667/0.808/0.950/0.142 ms
%ping 203.196.1.6
PING 203.196.1.6 (203.196.1.6): 56 data bytes
64 bytes from 203.196.1.6: icmp_seq=0 ttl=250 time=0.780 ms
64 bytes from 203.196.1.6: icmp_seq=1 ttl=250 time=0.573 ms
^C
--- 203.196.1.6 ping statistics ---
2 packets transmitted, 2 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 0.573/0.676/0.780/0.103 ms
%ping 202.106.0.20
PING 202.106.0.20 (202.106.0.20): 56 data bytes
64 bytes from 202.106.0.20: icmp_seq=0 ttl=55 time=1.168 ms
64 bytes from 202.106.0.20: icmp_seq=1 ttl=55 time=1.161 ms
^C
--- 202.106.0.20 ping statistics ---
2 packets transmitted, 2 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 1.161/1.164/1.168/0.004 ms
%ping qq.com
PING qq.com (58.61.166.142): 56 data bytes
64 bytes from 58.61.166.142: icmp_seq=0 ttl=51 time=37.044 ms
64 bytes from 58.61.166.142: icmp_seq=1 ttl=51 time=36.671 ms
^C
--- qq.com ping statistics ---
2 packets transmitted, 2 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 36.671/36.858/37.044/0.186 ms
%ping dl_dir.qq.com
ping: cannot resolve dl_dir.qq.com: Unknown server error
%uname -a
FreeBSD 7.0-RELEASE FreeBSD 7.0-RELEASE #0: Wed Nov 12 16:55:58 CST 2008 :/usr/obj/usr/src/sys/KERNDB i386
%

[Sundj]

I also telnet

On Linux

[sundj@WebServer ~]$ telnet dl_dir.qq.com 80
Trying 221.236.30.115...
Connected to dl_dir.qq.com (221.236.30.115).
Escape character is '^]'.
Connection closed by foreign host.
[sundj@WebServer ~]$ uname -a
Linux WebServer 2.6.9-5.ELsmp #1 SMP Wed Jan 5 19:30:39 EST 2005 i686 i686 i386 GNU/Linux
[sundj@WebServer ~]$


On FreeBSD

%telnet dl_dir.qq.com 80
dl_dir.qq.com: Non-recoverable failure in name resolution
%uname -a
FreeBSD 7.0-RELEASE FreeBSD 7.0-RELEASE #0: Wed Nov 12 16:55:58 CST 2008 :/usr/obj/usr/src/sys/KERNDB i386
%

[brucec@]

This isn't technically a bug, but it has been worked around in STABLE and will be in 7.1. See PR misc/128861 for details - http://www.freebsd.org/cgi/query-pr.cgi?pr=128862&cat=

[Sundj]

Originator: xjtdy888

Yes, he is my friend. He reported this bug to delphij.


Hahaha~
1. This is not a bug, ask qq.com to fix their domain name since
it's a clear violation of Internet STD 13 (RFC 1034). These
DNS administrators should be fired.
2. This has been worked around in all supported stable branches
and the workaround would be available in both 7.1 and 6.4
releases.

[Sundj]

Thank you all!

[DutchDaemon]

The RFC is pretty clear actually. Underscores are reserved characters that are not supposed to be in a fqdn at all.

I know, but I see a lot of applications 'allowing' it, like Squid and Firefox. Probably because huge sites like Blogspot and others allow their users to put underscores in their blog names (like groove_rider) and such. It's a bit of a Microsoft tactic, I guess: allow massive infractions on an RFC, and the RFC will be circumvented. Not good, but a reality.