At day's end, I suspended my laptop.
I took it home, ipconfig /release, ipconfig /renew, viola.
I VPNed in to work from home, no problem.
This AM, I suspended my laptop and came in to work.
Once here, I plug in, unsuspend
Oh, ok, ipconfig /release, ipconfig /renew, viola? No
Still no IP.
Pull power and battery, boot, nope.
Try another ethernet port. Nope.
So I went to my meeting, came back, it said that after 2 hours, it picked an IP.
Ping gateway? Nope.
Try more ports. Some are dead, others don't give IP.
I try a coworker who has a switch. I get an IP and it works like a champ.
Another laptop, on my drop, works like a champ.
I find out that our normal subnet is privately managed by our folks.
The people with switches are on a whole different subnet.
It's not only a different subnet, but it's a different switch, router, etc.
In surfing my settings, my ethernet adapter had filled in "Locally Administered Address".
Look under laptop, and the sticker doesn't match my presented MAC addr.
I cleared this, and renewed...
"The DHCP server has assigned you an address that belongs to someone else."
I rebooted, and viola. All is well.
Aparently, at some point, my old laptop's MAC addr made it's way in as a soft setting vs hard setting.
I replaced my laptop a while back for bad screen.
When the old one FINALLY came back, it was recently redeployed.
MAC Addr conflict on the same switch(es) = bad bad bad.
I still don't know why it was filled in, but it's lucky I noticed that.
Deskside didn't notice it, and I was preparing to reinstall my system.
Of course, that would have fixed the problem, but would have been a waste of reconfig time.