Arch Linux

lyfo

Member

Registered: 2014-08-22

Posts: 2

strange host resolution problem

First off, this is my first post so hi everyone! loving arch, loving the forums and the wiki. It's a testament to the wonderful documentation that I've got this far without a "newbie problem"

So on to business. Whenever pacman (or seemingly any other command line software, including for example the tex live installer) has to download anything, upon first trying to connect I get a "could not resolve host" error, but then if I try to connect again immediately afterwards it works. This is consistent and completely repeatable. So for a while I was running pacman twice whenever I wanted to do anything.

The workaround I'm currently employing is to have all mirrors appear twice in my mirror list, the first try on any of them fails, and then the second try succeeds. Spooky.

Here's my mirrorlist: (note the repetition, there are only three mirrors here)

## Score: 0.9, United Kingdom
Server = http://archlinux.mirrors.uk2.net/$repo/os/$arch
## Score: 0.9, United Kingdom
Server = http://mirror.bytemark.co.uk/archlinux/$repo/os/$arch
## Score: 1.5, United Kingdom
Server = http://mirrors.manchester.m247.com/arch-linux/$repo/os/$arch
## Score: 0.9, United Kingdom
Server = http://archlinux.mirrors.uk2.net/$repo/os/$arch
## Score: 0.9, United Kingdom
Server = http://mirror.bytemark.co.uk/archlinux/$repo/os/$arch
## Score: 1.5, United Kingdom
Server = http://mirrors.manchester.m247.com/arch-linux/$repo/os/$arch

and here's an example of the error:

➜  ~  sudo pacman -Syu
[sudo] password for lifo: 
:: Synchronising package databases...
error: failed retrieving file 'core.db' from archlinux.mirrors.uk2.net : Could not resolve host: archlinux.mirrors.uk2.net
error: failed retrieving file 'core.db' from mirror.bytemark.co.uk : Could not resolve host: mirror.bytemark.co.uk
error: failed retrieving file 'core.db' from mirrors.manchester.m247.com : Could not resolve host: mirrors.manchester.m247.com
 core                     113.6 KiB   492K/s 00:00 [#######################] 100%
 extra                   1775.4 KiB  1062K/s 00:02 [#######################] 100%
 community                  2.3 MiB  1124K/s 00:02 [#######################] 100%
:: Starting full system upgrade...

(after three failed attempts pacman tries again to connect to the first mirror, succeeds, and continues as normal.)

As far as I can tell there is no other problem with the internet at large, my browsing experience is unaffected, I can ping google on the first attempt. The only time it has actually been a real issue was installing tex live where I would keep getting host resolution errors a few minutes in and have to start again.

Now this is by no means a major issue but I've googled it to death and it is confusing me so I thought it'd throw it out there and see if anyone had any ideas...

UploadDownload

Member

Registered: 2014-08-26

Posts: 4

Re: strange host resolution problem

Can you run the "dig" command on a domain? such as:

 dig google.com 

lyfo

Member

Registered: 2014-08-22

Posts: 2

Re: strange host resolution problem

doesn't look like anything unusual, although I don't really know what a normal output from dig looks like

➜  ~  dig google.com

; <<>> DiG 9.9.2-P2 <<>> google.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 45680
;; flags: qr rd ra; QUERY: 1, ANSWER: 11, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4000
;; QUESTION SECTION:
;google.com.			IN	A

;; ANSWER SECTION:
google.com.		300	IN	A	173.194.41.166
google.com.		300	IN	A	173.194.41.160
google.com.		300	IN	A	173.194.41.168
google.com.		300	IN	A	173.194.41.165
google.com.		300	IN	A	173.194.41.164
google.com.		300	IN	A	173.194.41.167
google.com.		300	IN	A	173.194.41.169
google.com.		300	IN	A	173.194.41.161
google.com.		300	IN	A	173.194.41.162
google.com.		300	IN	A	173.194.41.174
google.com.		300	IN	A	173.194.41.163

;; Query time: 26 msec
;; SERVER: 192.168.1.254#53(192.168.1.254)
;; WHEN: Tue Aug 26 17:58:29 2014
;; MSG SIZE  rcvd: 215

if i try it on the mirror i get:

➜  ~  dig archlinux.mirrors.uk2.net
;; Got bad packet: FORMERR
70 bytes
68 10 81 20 00 01 00 01 00 00 00 01 09 61 72 63          h............arc
68 6c 69 6e 75 78 07 6d 69 72 72 6f 72 73 03 75          hlinux.mirrors.u
6b 32 03 6e 65 74 00 00 01 00 01 c0 0c 00 01 00          k2.net..........
01 00 00 02 58 00 04 53 aa 5e 03 00 00 00 00 00          ....X..S.^......
00 00 00 00 00 00                                        ......

but i don't know if that is expected...