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I am having Ubuntu 12.04.

DSL through pppoeconf(connecting at boot time) works without any problem but connecting through Network Manager stops some sites from (fully)loading in browsers ?

Disabling dnsmasq by commenting dns=dsnmasq line in /etc/NetworkManager/NeworkManager.conf is not solving the problem..

Thanks in advance.

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It's not ubuntu problem. It's called MTU (maximum transmission unit). MTU is very sensitive for pppoe connection. I am having same problem, not in ubuntu but my router. I am still looking for answer . – shantanu Jun 27 '13 at 21:39
@shantanu Yes, it's a widely known issue and is caused by a wrong path-MTU. Setting the right MTU at your side should not cause issues, but I've seen b0rked configurations at the ISP side. To solve this for TCP at your end you can use MSS clamping. See – gertvdijk Jul 14 '13 at 10:05
Have a look at Why can I not access and from Ubuntu but can do so from Windows? and check if you have similar symptoms. – gertvdijk Jul 20 '13 at 23:38

Open /etc/NetworkManager/system-connections/ and edit your DSL connection file, remove


click Save

problem resolved :D

share|improve this answer
How does this solve the issue in the question? The LCP echo is for detecting a dead link. Without this, a dead PPPoE at the other end will keep your connection open. I don't see how disabling this would fix the issue about websites not loading completely. – gertvdijk Jul 14 '13 at 10:02
bcoz i was having the same issue with network manager some sites like etc.. not loading, after remove lcp i can load all these sites – Linux21 Jul 14 '13 at 10:13
Okay, I'm glad it helped you out, just saying that I am frowning upon the solution - it has nothing to do with the symptoms. :P – gertvdijk Jul 14 '13 at 10:18

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