You can do a few things to get past this.
First see what changed electronically wise in your house in the last 3 weeks or items that was moved, check for lights that flicker dimmer = sign of bad electricity coming into your house, maybe dew to severe weather in local region.
Same for when you start the tumble dryer and dishwasher does the lights dip, tube light show this more than normal lights.
Set a static ip in the router 192.168.1.54 where cable / modem is 192.168.1.*
Or just set it to reboot say everyday at 4am or twice daily when lowest internet usage is used.
Or check the wall power supply as it can fluctuate and the transformer power cable / plug either gets a spike or a dip and can not compensate for it or long enough to get past this. This is happening with my RT-N16 on the same wall plug as the tv especially now with the winter starting.
I have had success with a lightning protector power strip and having the router transformer plug plug into this. Not all of them work the same so it is hit or miss testing.
Also check with a $3 wall socket tester thing from home depot if the wall plug is properly earthed as this is a big cause of issues and makes most lightning strips fail if wiring is incorrect and destroys sensative hardware like pc's / satelite tv decoders, routers / modems ......
Also heat and static build-up or radiation interference. This all sounds stupid but you would catch the culprit and then have a stable router. Router on or close to a old square box tv's / crt tv = no go or being on the same wall power outlet as the crt tv or washing machine / stuff like that.
Being on ch1 and some portable land line phones will interfere with this ch1 and cause disconnects from the internet as stupid as that sounds it happens. How this works = mystery but have changed channels where this happened and no more problems.
Best is to get something like a opti ss1200 for $20, a Automatic Voltage Regulator and plug your modem and router into that.
All this and shortest possible cable for the modem and using shielded cables / metal on side of lan cable fittings does help to get more out of your internet connection.
If this fails then get a new router from walmart and test if it does the same then the power line has issues if not then the old router has micro fractures in the pc board and it is dying slowly.
Somewhere in this you will find the answer, try the cheapest least invasive methods first.
It might be something simple like the wan and power cable connector needs some solder on all the loose joints. Ask the isp if they changed protocols or updated ipv4/6 or other hardware that is linked to your modem or the modem firmware as this could affect older hardware / software standards and getting it to work.
As the title says, the issue I've been having now for the past week or 2 now.
I'm currently running Firmware: DD-WRT v24-sp2 (09/23/11) stdkong.
I've used the latest Kong's Mod, and then Toastman's, and then when neither of those solved my issue, I even reflashed to the Stock Netgear firmware. No luck.
The issue seems to present itself at random intervals - it tends to appear to be working fine at first, and then sometime over the next 24 hours it loses the WAN IP (and thus, all internet access).
I've got both wired and wireless devices on the network and I've tried various combinations of them in an attempt to cut out variables.
Anything hooked up directly to my Cable Modem has no problem getting an IP (other than my router). I've spoken with my ISP twice and they've confirmed that they're not showing any issues on their end.
I've tried tinkering with the settings a bit, and then I even tried just leaving everything set to default settings. I was originally restoring my settings after flashing (I tend to work with Static IPs, Portforwarding rules, and DMZ items on my LAN) but gave up on that once the problems persisted.
I've done the 30-30-30-30 (and 60-60-60..) flashes (before and after new firmware), and while each time I tend to be able to get a WAN immediatly following, it so far hasn't stuck.
I've had this router for a couple years and this is the first real issue I've run into since flashing (I've used Kong's Mod for 80% of that time)
When the router has lost its WAN IP, using the WebGUI Release / renew IP option doesn't help.
I do have a second router in the house that I've used since for testing purposes and it worked flawlessly over the weekend, so again I'm pretty certain the issue is my router.
I'm just trying to figure out if it's time to go shopping for a new one or not.
I'm open to suggestions
You can do a few things to get past this.
Make sure to have the firmware on the SB6120 updated to the most recent version
There is a bug in anything before Firmware Name: SB612X-22.214.171.124-SCM01-NOSH
That could be part of the issue as i just for the most part been solving a similar situation
Then make sure you have the most up to date firmware for the rt-n16
That I would think take care of the issues
Is the firmware on your surfboard SB6120 the most recent firmware
A lot of people have had issues with this modem and router connections due to the firmware on the sb6120 that is before this version
192.168.100.1 should get you log on to the modem to check
Hope that helps
You have to contact Charter to get them to push out the firmware to you modem. Hopefully they have a web forum that you can use to contact them
I just did it with media com and have notice a better response overall
I found your post when searching for the exact same problem. What I ended up doing was:
Connect my PC directly to the modem,
/release and /renew,
Confirm internet on PC
Clone PC MAC into DDWRT
Worked like a charm for me.