Some sites do not open on Ubuntu 17.04 - what to do?

Question

linux

Some sites work through time (in most cases do not work).
Sites that do not work:
https://login.live.com (because of this, Skype does not start)
https://developer.mozilla.org
ping https://login.live.com
ping https://developer.mozilla.org

Tried different browsers.

Answer 1

The first ping should be used like this:
By specifying the protocol you will always get the host unknown.
I would check DNS:

nslookup developer.mozilla.org
и
nslookup developer.mozilla.org 8.8.8.8

Answer 2

https://github.com/systemd/systemd/issues/5755 - demolish ubuntu and install Devuan or something else "systemd free"

Answer 3

Go to the network interface settings, enter 1448 in the MTU field. Click save.
Don't thank

Answer 4

In the network settings, in the "cloned MAC address" column, click "random". Helped me.