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You're now in 192.168.1.100/24 instead of the previous 172.18.165.241/22 which fits the DNS server you always got.
So the DNS was correct, but the lease wasn't.
Are you still connected to the "library2" SSID?
Do you now have to enter some 2nd layer creds before the internet works?
Does the journal show you currently first get a lease in 172.18.165.0/22 and then switching to 192.168.1.100?
I'm trying to understand what's going on because I want to make sure that you're connected to the network you think you're connected to.
nb. that the default #53 DNS is NOT encrypted, so even when you're on a https connection, simple DNS queries can be recorded and manipulated.
https://en.wikipedia.org/wiki/Domain_Na … ing_issues
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