apt update failing because it can't connect to ppa.launchpad.net

Question

When I try to update using apt update, I get the following errors.

Err:10 http://ppa.launchpad.net/danielrichter2007/grub-customizer/ubuntu bionic InRelease
Could not connect to ppa.launchpad.net:80 (91.189.95.83), connection timed out Could not   connect to ppa.launchpad.net:80 (2001:67c:1560:8008::15), connection timed out
Err:11 http://ppa.launchpad.net/js-reynaud/kicad-5.1/ubuntu bionic InRelease
Unable to connect to ppa.launchpad.net:http:
Err:12 http://ppa.launchpad.net/tista/plata-theme/ubuntu bionic InRelease
Unable to connect to ppa.launchpad.net:http:
Err:13 http://ppa.launchpad.net/ubuntubudgie/backports/ubuntu bionic InRelease
Unable to connect to ppa.launchpad.net:http:
Err:14 http://ppa.launchpad.net/zeal-developers/ppa/ubuntu bionic InRelease
Unable to connect to ppa.launchpad.net:http:
Fetched 7,502 B in 31s (238 B/s)
Reading package lists...
Building dependency tree...
Reading state information...
1 package can be upgraded. Run 'apt list --upgradable' to see it.
W: Failed to fetch http://ppa.launchpad.net/danielrichter2007/grub-customizer/ubuntu/dists/bionic/InRelease  Could not connect to ppa.launchpad.net:80 (91.189.95.83), connection timed out Could not connect to ppa.launchpad.net:80 (2001:67c:1560:8008::15), connection timed out
W: Failed to fetch http://ppa.launchpad.net/js-reynaud/kicad-5.1/ubuntu/dists/bionic/InRelease  Unable to connect to ppa.launchpad.net:http:
W: Failed to fetch http://ppa.launchpad.net/tista/plata-theme/ubuntu/dists/bionic/InRelease  
Unable to connect to ppa.launchpad.net:http:
W: Failed to fetch http://ppa.launchpad.net/ubuntubudgie/backports/ubuntu/dists/bionic/InRelease  Unable to connect to ppa.launchpad.net:http:
W: Failed to fetch http://ppa.launchpad.net/zeal-developers/ppa/ubuntu/dists/bionic/InRelease  Unable to connect to ppa.launchpad.net:http:
W: Some index files failed to download. They have been ignored, or old ones used instead.

The thing is that I can visit these links from my web browser so it must not be a issue with the servers.

And I have tried forcing IPV4 only when updating to see if its IPV6 issue. Also I have tried removing all those ppas and adding them again.

Solution 1

Okay it is solved now, when I connected to the network in my college hostel. Was probably some issue with the ISP or router maybe.

UPDATE:

Ok I actually found out the issue and I thought it would be nice to add it to the discussion here so that other people might find it helpful.

The problem was that ipv6 was not enabled in my home internet modem. So I went to the modem configuration ip address and enabled it and the issue got solved in my home too.

It might also be the case that your ISP does not support ipv6, which is the case with BSNL in India, so look out for that too.

Solution 2

When I experience this (occasionally with no network changes), I find that using apt-get instead of apt works.

Comments

[Benoît]

Do you use a proxy server in your browser ?

[Allen]

No I do not use a proxy

[user535733]

If you can visit these links from your web browser, then you have conclusively demonstrated that the servers are working properly. One common cause is a stuck router: Try power-cycling your router.

[Allen]

I have actually tried downloading from different networks. From my mobile data through a wifi hotspot and from my home router

[izzulmakin]

it appears that ppa also stop serving the ipv4 address. when using ipv6 (default approach) and failed, it will try to use ipv4 but we will get Could not connect to ppa.launchpad.net:80 (2001:67c:1560:8008::19). - connect (101: Network is unreachable) Could not connect to ppa.launchpad.net:80 (91.189.95.85), connection timed out. Even if we force to use ipv4 only with Acquire::ForceIPv4 we will still get the 2nd part of that error

[Allen]

yeah. do check if your isp supports ipv6