This is why you don't have more IP address in your DHCP, when this happen, the system takes a public IP that don't works.
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"Two things are infinite: the universe and human stupidity; and I'm not sure about the universe.". Albert Einstein.
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Reply to saint19
I already forgot my lessons in Cisco. I was asleep back then. LOL!
You can try googling that out man, I'm sure there are online solutions offering an answer to your problem.