I am on kubuntu 15.04 with KDE 5.2.2 and I can connect to a network but I cannot access the internet. I can ping my local IP address and KDE Connect works just fine with my phone, but I cannot ping a website or go online via a browser. Akgregator, kmail, andother such tools are also down.

I have no idea what to do. This happens on more than one network and several reboots and removing/adding the connection have not helped at all. Any help helps. Thanks!

can you ping your router?

if yes: your router access / wifi settings do not permit you WAN access - that's something in the router (or you're entering eg. w/o a password and would require a password login - this can be controlled via the router IP or implicitly, ie. the router accepts a blank password, but you're then in guest mode)

if no: you're *not* connected to your netwrok, your phone is connected either adhoc or eg. via buetooth.

At home, I think I can. Not 100%. Right now I'm on an open network and I can ping other computers in the network and can connect to servers on the network but cannot get online. I can get online on any other computer in the network as well as my phone. My phone has data and bluetooth off.

your router access / wifi settings do not permit you WAN access

How do I allow WAN access, then? Thanks for the help!

That's done in the router configuration, but it's highly unlikely that yours *and* some public router are misconfigured this way.
How do you determine you cannot access "the internet"?
Can you ping 8.8.8.8 (googles DNS server)?

If yes, check (do not necessarily post!) the contents of /etc/resolv* - it likely means your DNS server is misconfigured.
If the router you connect supports dhcp, /etc/resolv.conf should contain the router IP.
You can try editing it (needs root permissions) and just ensure the nameserver line is

Code: Select all

nameserver 8.8.8.8


(this will use googles DNS server, usually your ISP will provide his own DNS server and there are tons of free DNS servers to use, but 8.8.8.8 is an easy to memorize and pretty reliable address

Well, "internet" is a misnomer perhaps. I mean stuff like this:
- Akregator doesn't fetch any feeds.
- Kmail doesn't display e-mails.
- Firefox doesn't load websites.
- wget cannot resolve host address.
- ping www.google.com says "unknown host"

Interestingly enough, I can actually connect to my work's VPN (from my work's network) and get online just fine that way (browser, e-mail, etc. works), but I only log into my work's VPN for, well, work stuff.

Anyway, if I log off and get onto a public network and ping 8.8.8.8 then it works just fine. If I check /etc/resolv.conf then I get a list of 5 lines with nameserver... Do I change all to 8.8.8.8?

just prepend a new line, so that "nameserver 8.8.8.8" is the first line.
"#" indicates a comment.
for the other entries, it might be intersting to check who that is and whether it's usually a nammeserver.

also notice that the file Might get rewritten (on reboot), so just manipulating it will show the cause and resolve the issue, but not be really a fix.

i assume neworkmanager is maintaining this in ubuntun- it might be buggy, but your system may be hacked or the vpn login manipulates the file and doesn't revert it.

Mmm. This worked. Thanks!

However, it is rather disconcerting. I can ping all of the addresses in nameserver from my laptop, but not from any other machines. Your comment about my machine being compromised---how would I be able to tell?

If there's no IP that looks fimiliar like "our private secret company DNS server" - just post the list.

It's not sufficient to be able to ping the IP (just means it's online) but it also needs to be running a DNS server:

Code: Select all

nmap -Pnp53 8.8.8.8


if it is, digging should work

Code: Select all

dig @8.8.8.8 google.com


Replace 8.8.8.8 with the actual entries; google.com can be any existing hostname (notably those you want to connect)