My grandson came over for a visit ...

[GreyGeek]

and as usual, he runs my Acer, because it is much faster, and gives me his to run.

His Acer is a Win7 & Kubuntu 14.04 dual boot, set to default on Trusty. I fired up Trusty and immediately noticed that his wireless connection (rtl8188ce running rtl8192ce) loops repeatedly, attempting to connect. No problem, I though. I'll just turn off the wireless and plug in my eth0 cable. The atl1 driver did the same thing with the eth0 connection. I was without an Internet. My Acer, which he was running, was rock solid on the ath9k wlan0 connection, as it usually is. My wife's Acer Aspire One 0D521 netbook connected and ran flawlessly.

I booted into the Win7 side on my grandson's Acer and encountered a similar problem. Under Win7 the Acer was no longer in the "HomeGroup" and the "Internet Group" made a connection of sorts, but without DNS, so firefox wouldn't browse. Attempts to add the wireless to the HomeGroup failed. It was attempting to assign an address in the 198.*.*.* range, which is not in the three blocks assigned to local networks (10.*, 172.*, 192.*) It appears that the DHCP wasn't pulling in the DNS for that reason. It allowed a partial connection in Windows but Kubuntu would have none of it. Since my wireless only assigns IP addresses in the 192.168.1.5-10 range I have no idea where that 198.* came from.

I went into the windows wlan0 properties and switched it to manual, using 192.168.1.2 as the IP address, 255.255.255.0 as the netmask and 192.168.1.1 as the gateway. I also added Google's DNS (8.8.8.8,8.8.4.4) to the DNS configuration and saved the setting. The wireless connected immediately as the homegroup.

I rebooted back into Kubuntu and manually set wlan0 IP and DNS the same way. The connection was immediately.
After I took my grandson home I gave the problem some thought. Since the DHCP in both Win and & Kubuntu were not work properly on my grandson's machine, both dhcp clients can't be faulty. That leaves the router. But, it was linking my Acer to the Internet properly and my wife's netbook connectedly seamlessly when I booted it up.

I decided to reboot the router. We'll find out tomorrow if my grandson's Acer connects like it used to do.

[SteveRiley]

Perhaps your router's DHCP quit working? If the IP address leases on your own machines haven't yet expired, they'll continue to work.

The 198 address is really weird... the whole netblock is owned by ARIN, and is subdivided across many networks. Do you remember any more of the address?

[GreyGeek]

Remember any more of the 198 IP address? Nah, if my memory were still that good I would have kept on as an admin here.

My router is set to renew DHCP leases every day, but I rarely reboot it and I've only done a power cycle one since I got TimeWarner's Internet service. I would guess that my last reboot was probably 3 or 4 months ago.
My grandson was scheduled to visit us again ("baby" sitting till his mom got back from Denver) yesterday. He never had any problem connecting but that was probably due to the fact that his wlan0 config is set to manual with the IP address I supplied and using Google's DNS service.

My router is set to give my Acer a static IP address of 192.168.1.111 using Acer's MAC. No time limit is given in that setting. Sometimes I will leave my Acer on for several days. My wife boots up her Netbook once or twice every day. It uses DHCP. As you suggested, she was probably logging back in on the same lease.

I have the router log disabled so there is no audit trail of any connection attempts on either side. I would be surprised if I saw this event happen again. So, even though the DHCP leases renew every 24 hours I will probably reboot the wireless occasionally just to be sure. I should mention that my Cisco E2500 wireless router is running DD-WRT's firmware and so far I have had no problems would could be laid on it. This could be one.