Tuesday, October 10, 2017
Destination Host Unreachable for one machine but not another on same network?
I had a miserable time trying to work out why my own PC wouldn't show me pages from w3schools.com while other PCs on the home network were fine. And other pages on my PC were fine too.
It wasn't a browser issue.
After checking DNS and the hosts file, I eventually twigged what was wrong. My subnet mask.
The site w3schools.com resolves to an IP address starting "192." - and I had (erroneously) set my subnet mask to 255.0.0.0 - result: my PC thought any "192." was local
I had meant to set the mask to 255.255.0.0 - which gives access to devices pre-set to 192.168.anything, but allows access to external sites with IPs of 192.anything-but-168.xxx.xxx
Silly me
It wasn't a browser issue.
After checking DNS and the hosts file, I eventually twigged what was wrong. My subnet mask.
The site w3schools.com resolves to an IP address starting "192." - and I had (erroneously) set my subnet mask to 255.0.0.0 - result: my PC thought any "192." was local
I had meant to set the mask to 255.255.0.0 - which gives access to devices pre-set to 192.168.anything, but allows access to external sites with IPs of 192.anything-but-168.xxx.xxx
Silly me
