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#1 Ph1b3r0pt1c

Ph1b3r0pt1c

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Posted 26 August 2013 - 21:27

I have been having all kinds of problems with my ISP, and they keep trying to fix it, tell me its fixed, and nothing has changed. So here is my question. I can check my DHCP lease time from them, and see its set at 30 mins. I know that DHCP usually requests a link at half the time its set to expire. That being said, my DHCP lease times swing from 30 minutes to 3 hours, then back to 30 mins. I am stupid in this area, but would that be the reason for the constant disconnects, and 100% packet loss I randomly get? This is WiMAX service, and I have nothing else I can switch to, so unless I can convince them there is a problem I am pretty much screwed. One day after they do something, it works fine for a day. The next day its down more than it is up. The dude that comes out here tells me that the signal strength is perfect, but I am not sure about that DHCP lease time jumping around like it is. Can anyone shed any light on this and call me a moron?

 

Like right now its:  

 Lease Obtained. . . . . . . . . . : Monday, August 26, 2013 4:23:20 PM
 Lease Expires . . . . . . . . . . : Monday, August 26, 2013 7:23:20 PM

 

I JUST renewed it again, and now it says:

 Lease Obtained. . . . . . . . . . : Monday, August 26, 2013 4:29:00 PM
 Lease Expires . . . . . . . . . . : Monday, August 26, 2013 4:59:00 PM

 

Am I just retarded or is there a problem?




#2 +BudMan

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Posted 26 August 2013 - 21:38

Are you getting your lease from different server.. That should also be listed

Lease Obtained. . . . . . . . . . : Monday, August 26, 2013 9:37:45 AM
Lease Expires . . . . . . . . . . : Tuesday, August 27, 2013 3:37:46 AM
DHCP Server . . . . . . . . . . . : 10.56.144.20

30 minutes seems quite low.. curious if just different lease time configured on different servers.

So when you get disconnected, you no longer have an IP? Or it changes to APIPA? 169.254.x.x

It is possible that your lease is not renewing, and then finally expires and then yeah you would loose connectivity.

But if you have an IP.. no your lease time has nothing to do with your connectivity at that point in time.

Keep an eye on it, does the dhcp server IP change? You can force renew with ipconfig /renew or ipconfig /release and then /renew etc.. to see if you can cycle through who is giving you a lease and the amount of time. And if the lease time is from 1 of their dhcp servers, etc.

If they are running a 30 minute lease, I would have to think they are really close to max if not exceeding number of Ips they can hand out.. So they want to make sure they get their IP back to hand to someone else quickly after you disconnect.

So yeah I could see that if 30 minutes was set on purpose they might have an issue with congestion???

What OS are you using? I can look to see if way to adjust the requested lease time. Linux is quite simple, but have never needed to look into how to adjust option 51 on the dhcp client in windows to ask for a specific lease time. Doesn't mean the dhcp server will give it to you ;) but it might be possible to ask for longer 1.

#3 Roger H.

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Posted 26 August 2013 - 21:53

My ISP does this thing where if you just got a new IP it's set for as little as 1hr. When the request to renew though it gets extended the full way (6hrs - technically 2 days - weird... i'll explain it one day.LOL)

 

So maybe whenever you are force refreshing they just dump you with a temp lease which then gets renewed if you still need it and for the full longer time.



#4 OP Ph1b3r0pt1c

Ph1b3r0pt1c

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Posted 26 August 2013 - 22:01

I've been having all sorts of problems. The server IP doesn't change, its stayed the same, but the lease time has jumped around. Yesterday it stuck on renewing for 4 hours before I got an ip, but when I set it as static, and used the same IP (It never changes) everything worked fine until I started having 100% packet loss everywhere. My MAIN IP to them has never changed.



#5 xreyuk

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Posted 26 August 2013 - 23:56

I know this is the UK, but I sometimes have a problem with my ISP where I get the same symptoms as you and have to release and renew the DHCP lease on my DSL.

 

So yes, it could the cause for your packet loss etc.



#6 OP Ph1b3r0pt1c

Ph1b3r0pt1c

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Posted 27 August 2013 - 02:23

Ive also noticed when ive been connected for say 20 mins, ill be doing something, get 100% packet loss, have to renew to get back online. I may cancel this crap and just deal with no inet connection untill ATT decides to fix their crap (which will be never) or pray that new wave communications will run cable an additional 2 miles to my house.



#7 +BudMan

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Posted 27 August 2013 - 11:07

You can not set your IP as static.. Unless your isp has given you one.. It might work for a while, but as soon as they hand out that IP since there is no dhcp lease on it. Your going to have issues.