Arch Linux

Summary and Info:
Actually connected behind a router that has proper DNS server working, does not allow pacman to check out for the correct DNS server as of timeout (after more than 10000 ms)
Using a different DNS server in "resolv.conf" (As Google ones) solves the problem.
Still, using 'drill' to find the DNS mapping gives the answer in way less time (under 100 ms usually)

Steps to Reproduce:
* Use a router that sets itself as DNS server (that actually redirects to other servers)
* Running 'pacman -Syy' will give some errors
* Running 'drill NOT_SOLVED_MIRROR' will work

Example:
---
$ LANG=C sudo pacman -Syy
:: Synchronizing package databases...
core 121.8 KiB 523K/s 00:00 [-----------------------------------------------------] 100%
extra 1808.1 KiB 3.73M/s 00:00 [-----------------------------------------------------] 100%
community 2.9 MiB 5.26M/s 00:01 [-----------------------------------------------------] 100%
error: failed retrieving file 'antergos.db' from mirrors.antergos.com : Resolving timed out after 10520 milliseconds

...

$ drill mirrors.antergos.com
;; ->>HEADER<<- opcode: QUERY, rcode: NOERROR, id: 25368
;; flags: qr rd ra ; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 4
;; QUESTION SECTION:
;; mirrors.antergos.com. IN A

;; ANSWER SECTION:
mirrors.antergos.com. 56 IN A 82.192.75.147

;; AUTHORITY SECTION:
antergos.com. 172556 IN NS lakas.ns.cloudflare.com.
antergos.com. 172556 IN NS dahlia.ns.cloudflare.com.

;; ADDITIONAL SECTION:
lakas.ns.cloudflare.com. 147016 IN A 173.245.59.194
lakas.ns.cloudflare.com. 72579 IN AAAA 2400:cb00:2049:1::adf5:3bc2
dahlia.ns.cloudflare.com. 55334 IN A 173.245.58.89
dahlia.ns.cloudflare.com. 139327 IN AAAA 2400:cb00:2049:1::adf5:3a59

;; Query time: 6 msec
;; SERVER: 192.168.1.1
;; WHEN: Sun Oct 18 22:37:14 2015
;; MSG SIZE rcvd: 197
$
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