Networking – Fixing Website Access Issues in Ubuntu 13.10

13.04networkingWordpress

Something's wrong with Ubuntu. Since I've upgraded to 13.10, I can't access some websites for no apparent reason.

I've tried everything imaginable to solve this problem :

  • Made sure that MTUs are the same,
  • Disabled IPv6 in both the network manager and used browsers,
  • Deactivated my network keys,
  • DMZed my computer,
  • Used other DNS like Google and OpenDNS,
  • Checked that no firewall was running my computer …

And it's the same result. I even tried to reinstall Ubuntu a couple of times, but no luck.

The most annoying thing about it is I can't access wordpress.org! So, there's no way it could be an ISP restriction of some kind.

When I use a VPN, I can access pretty much anything.

I'm really frustrated because I have to use wordpress.org very often.

Any clue?

ifconfig

adame@adame-ws:~$ ifconfig
eth0      Link encap:Ethernet  HWaddr 00:26:18:3d:b0:7c  
      inet addr:10.42.0.1  Bcast:10.42.0.255  Mask:255.255.255.0
      inet6 addr: fe80::226:18ff:fe3d:b07c/64 Scope:Link
      UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
      RX packets:8024 errors:0 dropped:0 overruns:0 frame:0
      TX packets:7966 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:1000 
      RX bytes:684480 (684.4 KB)  TX bytes:616608 (616.6 KB)

lo        Link encap:Local Loopback  
      inet addr:127.0.0.1  Mask:255.0.0.0
      inet6 addr: ::1/128 Scope:Host
      UP LOOPBACK RUNNING  MTU:65536  Metric:1
      RX packets:8222 errors:0 dropped:0 overruns:0 frame:0
      TX packets:8222 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:0 
      RX bytes:568269 (568.2 KB)  TX bytes:568269 (568.2 KB)

wlan0     Link encap:Ethernet  HWaddr 00:19:70:40:85:eb  
      inet addr:192.168.2.3  Bcast:192.168.2.255  Mask:255.255.255.0
      inet6 addr: fe80::219:70ff:fe40:85eb/64 Scope:Link
      UP BROADCAST RUNNING MULTICAST  MTU:1464  Metric:1
      RX packets:123705 errors:0 dropped:0 overruns:0 frame:0
      TX packets:98141 errors:0 dropped:0 overruns:0 carrier:0
      collisions:0 txqueuelen:1000 
      RX bytes:94963545 (94.9 MB)  TX bytes:10387470 (10.3 MB)

/etc/hosts

127.0.0.1   localhost
127.0.1.1   adame-ws

::1     ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters

tracepath wordpress.org

1:  adame-ws.local                                        0.092ms pmtu 1500
1:  192.168.2.1                                           1.300ms asymm  2 
1:  192.168.2.1                                           1.060ms asymm  2 
2:  no reply
3:  no reply
4:  no reply
5:  no reply
6:  no reply
7:  no reply
8:  no reply
... keep on going like that

ping wordpress.org

adame@adame-ws:~$ ping wordpress.org
PING wordpress.org (66.155.40.250) 56(84) bytes of data.

--- wordpress.org ping statistics ---
10 packets transmitted, 0 received, 100% packet loss, time 9071ms

Best Answer

Check your router's hardware firewall for block-site rules; you can access it by visiting the router's ip from your browser in the form 192.168.x.x, try:

  • 192.168.0.1
  • 192.168.1.1
  • 192.168.1.25x etc.

Write ifconfig (ENTER) in a console (xterm is fine) and watch the form of the inet address camp, you will need to edit only the last digits to find your router's ip.
You will need to know the password and the user (ex. admin admin, password password, admin password ecc. if you left the default). If you don't know there is a list online, google it...
You must own the router. ;-)
If there is no firewall block - strange - run form a console sudo nano /etc/hosts and remove any line with wordpress inside. Do not edit other lines, it can cause software problems.
A diagnostic action is running tracepath wordpress.com to discover where is the block, if it is a total block and not an http-only block.
Let us know by commenting under here, you can be useful to the community.
Nice evening, I will help you if you need more help.

EDIT for Adame: I must use a solution valid for all users, so you will need patience, network problems are hard to solve.
Execute in a terminal:

echo "127.0.2.X HOSTNAME" >> toadd.txt

echo "127.0.0.1 localhost" >> toadd.txt

(replace hostname with the output of the hostname command and X with the end of your current IP, you can see it in ifconfig)
then edit /etc/hosts as root (use sudo YOUREDITORNAME /etc/hosts and add on top the content of toadd.txt).
Delete toadd.txt :)
Now the first problem should be fixed.
Check if your hosts file is like this:

127.0.0.1 localhost

Y.O.U.R.I.P YOURHOSTNAME

and a comment line.

Other argument.
The ping isn't a valid check because a modern and well configured server will discard your pings to avoid ping bounce network attacks. For example my ping fails on wordpress.
ICMP Ping is good only for well known servers!
But, tracepath shows that no intermediate server receives your ping, and this is strange, because after your router the ping gets lost but continues to "hop"... are you using the network of your factory? If it's it, you can be behind a blocking intermediate server and you will need to use a proxy.
If this isn't you case, let's continue by ignoring tracepath (the path changes always, but your network path appears to be faulty).
Do a next step and try to do from a terminal wget wordpress.com and after that ls -lh: if you see an index file in html format which is greater than 10kb (may change in future) the problem is in your web browser (bad extensions or misconfiguration), if you don't, try other two times.
If you get a good index file (try to open it with a browser by double-clicking it) and you can see the webpage, simply disable ALL extensions in your browser and after that reinstall it.
If you can't get a good index file the problem is in your network.
Here the hard procedure if you didn't solve:

  • Disable any proxy set in your browser and remove any instance of Tor and Privoxy, or of other distributed anonymous network systems. Reinstall them later if they aren't the problem, they are good for your privacy.
  • If it doesn't work change the DNS in your router (not in your PC) to Google DNS (in Google we trust & we find the DNS ip) and try. SUGGESTION: leave the Google DNS, they are always good.
  • If it doesn't work let's do a last check you can try to use a transparent proxy (anonim are slow) to re-route your traffic to wordpress: if it goes a server in the newtork hop path is faulty or your ip range is banned. If it doesn't function you may have a block inside your network.

    It's the best I can do with the information you left, good luck. Let me know. :)
    PS: a suggestion, for a proxy list search on google and pick a proxy with LOW ping and HIGH uptime.
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