Anyone configure static IP successfully? - Comcast XFINITY (2024)

djeff

Member

2002-Feb-16 1:40 pm

I'm just curious. Last weekend, I was having problems getting to the DHCP server (what else is new...) so I configured my IP staticly - I kept on pulling the same one like I used to with @home, so I figured why not. I was up and running well all week in static config.

My DHCP lease was set to expire today. Unfortunately, my connection went down, so I went back to DHCP to see if that would get me back on. As it turns out, that wasn't the problem, but by switching back to DHCP, I 'reset' the clock on my lease to next Saturday.

Anyone been configed static and working for over the one week lease period with the same IP without any problems? I'm pissed that I reset mine, 'cause I wanted to get that answer myself.

· actions · 2002-Feb-16 1:40 pm ·

Blam

Premium Member

2002-Feb-16 1:43 pm

· actions · 2002-Feb-16 1:43 pm ·

djeff

Member

2002-Feb-16 2:11 pm

· actions · 2002-Feb-16 2:11 pm ·

evansc to djeff

Premium Member

2002-Feb-16 2:32 pm

· actions · 2002-Feb-16 2:32 pm ·

Bill_MI to djeff

MVM

2002-Feb-16 2:41 pm

Just some input. If you have an outstanding DHCP lease static settings should always work. Your packets really cannot be discerned from those coming from the same entity that took out the lease - IF they all match, of course.

You can think of DHCP as adding a miniscule amount of overhead to get your settings for awhile. Between these DHCP events you look exactly like a static setting. No difference. Wow what a concept!

Areas may differ but best I can tell in a limited amount of renewals (3 so far) DHCP renews the same IP if it's available. To make it NOT available seems to take releasing it for some significant amount of time (I observed 5 minutes was plenty here). DHCP clients won't do that - they negotiate with time to spare, in fact.

I truly think some IP changes people report MAY be due to network burps, not by design. Or PCs shut down at DHCP key event times - if you get what I mean.

Bottom line: Why not let DHCP automatically renew for you at the fastest possible? Static settings are thought of as something they are not - mainly a way to retain the same IP for awhile. Quite the opposite. Static settings only exist because of DHCP leases coordinated with the cable modem security system - not the other way around. Static settings also causes surprise disconnects while running a proper DHCP client should prevent this.

Of course, Comcast is stabilizing things and funny things may occur. But I really think there's so much misinformation as a result the customers are hurting themselves in the process.

My 2 Cents.

· actions · 2002-Feb-16 2:41 pm ·

Blam to djeff

Premium Member

2002-Feb-16 2:43 pm

said by djeff:LOL - at least I know I'm not alone... Tks Blam!

I had initially DHCP'd the address with a FreeSCO disk when I first transitioned on the 7th, but I definitely didn't want all the stuff on my Red Hat firewall machine to go to waste!

BTW, where I live (in a hi-rise), I can see all the way almost to Willow Grove before the hills kick in. I can at least see up to those big tanks on the hill on Easton Rd. in Roslyn if you know that area. LOL

· actions · 2002-Feb-16 2:43 pm ·

Blam to Bill_MI

Premium Member

2002-Feb-16 2:51 pm

said by Bill_MI:Static settings are thought of as something they are not - mainly a way to retain the same IP for awhile. Quite the opposite. Static settings only exist because of DHCP leases coordinated with the cable modem security system - not the other way around. Static settings also causes surprise disconnects while running a proper DHCP client should prevent this.

I have been on Comcast since ~July 1999, have NEVER used DHCP until the transition, and NEVER lost an IP due to something other than them resetting my account (normally as their supposed "solution" to what was ALWAYS a network outage - thus the reset had been UNNECESSARY).

If an ISP has a sufficient class of network with a sufficient number of available IPs for their subscribers, than DHCP is really unnecessary, other than making it easier for the average user to get on the network quickly without having to manually configure the necessary routing servers, DNS servers, etc. The best use for DHCP was for those dialup providers who had only a limited number of IPs and alot of intermittant users needing one at the time of connect.

· actions · 2002-Feb-16 2:51 pm ·

Bill_MI

MVM

2002-Feb-16 3:17 pm

Blam, remember that the evolution of cable was rocky. The original design (of @Home at least) was all via DHCP. On the old systems, DHCP servers were flakey - sometimes because of incorrectly configured customer systems and sometimes because they were just plain lousy. What resulted was local support going to static settings for years as a bandaide. It stuck. Pretty soon it became automatic. This meant linking customers to IPs or all hell would break loose from a support standpoint.

Now, Comcast attempts the ideal DHCP solution again. This time it's a patchwork of systems as before but they're giving it a go. Many strange things may happen (the older the system you're on the stranger it will probably be).

I don't think you'll find the 1-customer-1-IP model isn't there because of lack of IP addresses but because the administrator wants to move blocks of addresses and not individual ones as customers change. It's a routing/IP-block thing, not the "overbooked" model of a limited number of addresses.

I just released my IP for 10 minutes and still got the same one back. It could be the different client I'm using or the fact other customers in the area just aren't grabbing IPs at an alarming rate like a few weeks ago after the transition (shrug). I'll release for an hour and see what happens.

Still, do you see why setting static in this environment doesn't guarantee a thing? Areas where it works for extended amounts of time are probably just as likely to get the same IP over and over via DHCP. But because it works in one area doesn't mean other, more dynamic areas, will do the same.

New info: I released my IP for 2.5 hours and STILL got the same one back. I wonder if something's changed or it's now stable since a zillion customers are not grabbing IP addresses all the time like just after the transition.

[text was edited by author 2002-02-16 18:11:16]

· actions · 2002-Feb-16 3:17 pm ·

Blam

Premium Member

2002-Feb-18 9:37 am

Sorry I didn't see your response Bill - I was bopping around DSLR yesterday (plus on other tech forums elsewhere).

In my case, I *live* in Comcast Headquarters territory, my system was brand new from the ground up (fiber in the street and all) at the time Comcast built it here in '98. Plus I was in 1 of 3 pilot test areas for internet service in Philly. My cable provider has ALWAYS been Comcast over the past 10 years or so (with Comcast getting into the ISP business here several years ago). So to me, it's everyone else that has patchworked into MY system.

When I first signed up in '99, I had excellent service with very few outages. However, when Comcast decided to start buying up little cable systems here and there, then began contracting out tech support (ALL my tech support used to be local and most were *nix aware), THAT'S when the service began to take a nose dive. I'm sorry, but this is true. This last merger/buyout was the straw that broke the camel's back. Comcast was a nice and friendly hometown operator here, but apparently one with BIG goals for the future.

The use of a static IP for me had nothing to do with DHCP not working or being flakey. It had to do with the fact that I DON'T put windoze boxen out on the net. Pure and simple. I use a linux NAT/firewall box, and since I have an older distro, the dhcp client for that old version was not robust (the newer iterations of my distro have a version of dhcpcd that works just fine).

If a provider has enough IPs to go around based on some average number of users on at a particular moment, then they have the luxury of setting longer leases. In any case, the average windoze user dutifully powers off their machine overnight and might not power it back on until late afternoon or evening. I, on the other hand, DON'T power off (with *nix, it's unnecessary), and routinely keep 300+ day uptimes depending on the power situation in my building and whether an outage would surpass my UPS's ability to hang on that long.

As an FYI, I'm still up with the same address set statically after 7 days. Hopefully it'll stay that way.

· actions · 2002-Feb-18 9:37 am ·

KurosPaladin to djeff

Member

2002-Feb-18 9:51 am

Well, I can say I'm not too happy with the DHCP services in Waterford, MI I have received three different IPs within 6 hours! My cable modem is hooked up to a Linky router, which is rarely power-cycled. I have yet to keep the same IP for more than 6 days, so to me it looks like Comcast is doing what they can to prevent users from getting the same IP each time they DHCPREQUEST. It makes no sense to me, either, since I can't understand why the DHCP server would deny a DHCPREQUEST for a specific IP, unless the server is instructed to move it's pool of IPs around every few days.

At least I'm in the same class network each time, so if I just try 254 addresses, I eventually find mine.

· actions · 2002-Feb-18 9:51 am ·

Blam

Premium Member

2002-Feb-18 9:55 am

· actions · 2002-Feb-18 9:55 am ·

zpon to KurosPaladin

Member

2002-Feb-18 10:13 am

· actions · 2002-Feb-18 10:13 am ·

tenbase to djeff

Member

2002-Feb-18 10:19 am

· actions · 2002-Feb-18 10:19 am ·

KurosPaladin to Blam

Member

2002-Feb-18 10:23 am

Yup, I'm aware of the Linky/Comcast situation. I'm at 1.40.2. I did have 1.42.3 (or was that 1.43.2?) for a brief period of time, but downgraded back to 1.40.2 because I WAS having serious problems with the newest version.

Well, I'm not running any servers that I need a static IP, but it would be nice to have a static IP because I do telnet in once in a while from remote locations.

· actions · 2002-Feb-18 10:23 am ·

Wageslave to tenbase

Premium Member

2002-Feb-18 10:24 am

said by tenbase:Personally I could care less and I also believe IPs should (and probably are) tied to MACs or hostnames, but for those of you configuring as static, please be aware that "hoarding" an IP can be considered a denial of service and can get you a nastygram from the AUP team.

It IS tied to a MAC address, and doing that WILL get you a nastygram, if not a deactivated modem. *shrugs*

· actions · 2002-Feb-18 10:24 am ·

tenbase

Member

2002-Feb-18 10:29 am

· actions · 2002-Feb-18 10:29 am ·

Blam to KurosPaladin

Premium Member

2002-Feb-18 10:38 am

Kuros - there's another post that I just read here at this forum about someone who downgraded even further to 1.39 or something and so far has found it stable. You might want to try that.

And I truly hope that this forum doesn't suddenly fill up with pseudo-Comcast police out to make a name for themselves. I don't know what the heck "IP hording" is supposed to mean, but the term's usage for something other than attempting to obtain more IPs than was paid for, sounds ridiculous.

I PAY for an IP to access the internet, whatever it might be. I PAID for 2 IPs up until December in fact, but due to the "NEW Comcast"'s fsckup during an outage in my area and due to the ever-eternal and USELESS reprovisioning of my modem to somehow fix a network problem, the other IP was lost in the process and no tech could get it back. At this point, I have to wait until the transition dust settles in order to do so.

So please spare the lectures and get on with your lives.

· actions · 2002-Feb-18 10:38 am ·

tenbase

Member

2002-Feb-18 10:46 am

Nobody is trying to "pseudo police" anything. I am simply trying to make people aware that the potential exists for Comcast to get their panties in a bunch because some of us choose to circumvent their ratty DHCP servers.

I certainly understand your perspective but you definitely don't need to be taking that tone with me or anyone else on this forum.

· actions · 2002-Feb-18 10:46 am ·

Blam

Premium Member

2002-Feb-18 11:01 am

said by tenbase:Nobody is trying to "pseudo police" anything. I am simply trying to make people aware that the potential exists for Comcast to get their panties in a bunch because some of us choose to circumvent their ratty DHCP servers.

I certainly understand your perspective but you definitely don't need to be taking that tone with me or anyone else on this forum.

Forgive the tone but there's been too much "holier-than-thou" attitudes here of late and I know that 99% of the average computer-owning, internet-connected users DON'T know what the heck DHCP is, can barely operate their windoze, and wouldn't even know what the heck we're talking about. They follow the instructions given them from Comcast for configuring their windoze boxen for DHCP, and go on with their business, whether it works or not.

For those of us who know more about networking than even the average Tier 2 or Tier 3 support, and who strive to be good "network neighbors" by not peddling warez or otherwise using up bandwidth with continual gigabytes-worth MP3 downloads and such, I think the preaching is uncalled for.

· actions · 2002-Feb-18 11:01 am ·

tenbase

Member

2002-Feb-18 11:17 am

· actions · 2002-Feb-18 11:17 am ·

mcssmcsd to djeff

Member

2002-Feb-18 11:43 am

· actions · 2002-Feb-18 11:43 am ·

Morac to djeff

Member

2002-Feb-18 1:11 pm

In some places it your ip address appears to be tied to your network card's MAC address. In other places it appears random (my brother has already had at least 2 ips already).

If you switch to static IP addressing and your DHCP lease expires the server is then allowed to assign the same ip address to someone else.

Whether it does or not depends on many factors such as how many new customers Comcast is signing up, how many free ip addresses they have, how the server is set up, ect.

For example my netmask is 255.255.248.0 which means my there can be 2045 (2^11 - 3) ip address on my local subnet. This means I can theoretically be assigned any one of 2045 possible ip addresses. So far I've always been assigned the same one, but there is nothing guarenteeing I will be. In fact if and when Comcast subscribes their 2046th Customer (possibly less if some customers buy multiple IP addresses), my IP address will have to change (or at least my netmask will).

It basically comes down to this. If your DHCP assigned IP address never changes then making your computer use static address won't gain you anything (assuming the DHCP server doesn't go down - in Windows XP you can assign a ip address to use if it does so just assign your current ip).

If your DHCP assigned IP address does change, then making your computer use a static IP address will your net connection to fail.

Either way I agree with Bill_MI using static addressing doesn't buy you anything special and can only hurt you.

· actions · 2002-Feb-18 1:11 pm ·

Bill_MI to Blam

MVM

2002-Feb-18 1:33 pm

said by Blam:In my case, I *live* in Comcast Headquarters territory, my system was brand new from the ground up (fiber in the street and all) at the time Comcast built it here in '98. Plus I was in 1 of 3 pilot test areas for internet service in Philly. My cable provider has ALWAYS been Comcast over the past 10 years or so (with Comcast getting into the ISP business here several years ago).

Gotcha, Blam. You missed all the fun of having *NO* local expertise for years, a level 1 support barely versed in Windows-setup-screens-only, well versed in how to avoid fixing local problems followed by level 2 hell-bent on "it's not our problem".

I think all Comcast started Motorola. The behavior on a friend's CyberSurfer seems to be a patched-up "make it work" so leases may be stable. Are you converted DOCSIS? In fact, I bet Comcast is finding this is the best way to set 'em all - Win32 DHCP clients may be too agressive.

*nix is stable, for sure, but I've been running NT almost since it started to be stable (NT 3.01). My box delegated to server stuff is running Win2KPro, BIND, Apache, Mercury Mail, BPFTP, Syslog stuff and a bunch of other things. Last time I booted it was Dec 22, 2001. My take on the Win32/*nix debate is "it's ONLY software!" (I'm a hardware guy ).

· actions · 2002-Feb-18 1:33 pm ·

Slinger to djeff

Member

2002-Feb-18 1:43 pm

I believe well-mannered DHCP servers hand out IP addresses on a least recently used basis. When you release an address it goes to the back of the list. When you renew a client, it first tries to give you your old IP back, failing that it gives you the oldest in the list.

Odds should be pretty good that you'll keep the same IP as long as Comcast has reserved a sufficient number of IPs so that all of their users can have their own. I know that here in Montgomery Co. MD, right after the transition there were not enough to go around, which is why some people could not get one and could not get online. The smaller the pool, the lower the odds you'll get yours back.

If you are having trouble either (A) keeping the same IP address or (B) getting one at all when everything else is configured OK, the most likely cause of the problem is a shortage of IP addresses.

· actions · 2002-Feb-18 1:43 pm ·

Blam to Morac

Premium Member

2002-Feb-18 2:05 pm

said by mkraft:If your DHCP assigned IP address does change, then making your computer use a static IP address will your net connection to fail.

Exactly. And thus those who do this must be ready to blap for an address once again.

quote:Either way I agree with Bill_MI using static addressing doesn't buy you anything special and can only hurt you.

Unfortunately, for those of us who run Distributed Computing projects, it DOES "buy" us something. The ability to remotely monitor our machines' progress/functionality while they are processing work.

It also helps for those who game and perhaps want to game with a neighbor on their node.

I try to keep an open mind as to what OTHER possibilities and reasons there are for those people who would prefer static vs dynamic IPs - and those possiblities DON'T always involve serving up warez and other illegal crap over the line. Some of us don't just surf the net looking for recipes or to email the latest pic of the grandchild to grandma. We make use of the connection for "volunteer" purposes in order to support some cause.

I wish people would realize this.

And I hope no one comes up with "well get DSL" or some other such comment because many of us live in areas or building types (I'm in a hi-rise) that may not or cannot connect to alternatives other than analog dialup.

· actions · 2002-Feb-18 2:05 pm ·

Epyon9283 to djeff

Premium Member

2002-Feb-18 2:23 pm

· actions · 2002-Feb-18 2:23 pm ·

davehay$
join:2001-12-31

davehay$ to djeff

Member

2002-Feb-18 6:23 pm

· actions · 2002-Feb-18 6:23 pm ·

Morac to Blam

Member

2002-Feb-18 7:34 pm

said by Blam:Exactly. And thus those who do this must be ready to blap for an address once again.

Well also if someone else get's assigned your old IP address and you have your machine statically set up to use that IP address then neither you nor your neighbor's connection will work. And in this case its your fault.

said by Blam:Unfortunately, for those of us who run Distributed Computing projects, it DOES "buy" us something. The ability to remotely monitor our machines' progress/functionality while they are processing work.

Many of the DC projects I've seen let you track by an account name (usualy e-mail address) in case you are using multiple computers with multiple IP addresses.

said by Blam:It also helps for those who game and perhaps want to game with a neighbor on their node.

There are many services out there that will allow you to map a name address to a changing IP address (such as dyndns.org and no-ip.com) and they can be set up to change the moment your IP address changes. Best of all they're all free.
And if you always get the same IP address through DHCP, just give your buddy that address.

· actions · 2002-Feb-18 7:34 pm ·

Blam

Premium Member

2002-Feb-18 7:47 pm

said by mkraft:

Well also if someone else get's assigned your old IP address and you have your machine statically set up to use that IP address then neither you nor your neighbor's connection will work. And in this case its your fault.

And might I ask the chances of that realistically happening? AND are you aware of how windoze (especially 9x) has a tendency to NOT release an IP even when rebooted and manually forced to request one? So I can imagine what should be happening on this network with all the windoze boxen...

quote:Many of the DC projects I've seen let you track by an account name (usualy e-mail address) in case you are using multiple computers with multiple IP addresses.

And many don't. Sorry but I run at least 7 different projects on 15 machines - some of which have multiple projects running on the same machine.

quote:There are many services out there that will allow you to map a name address to a changing IP address (such as dyndns.org and no-ip.com) and they can be set up to change the moment your IP address changes. Best of all they're all free.

I'm aware of those services and it sounds to me like something that would violate a TOS. Wouldn't you agree?

quote:And if you always get the same IP address through DHCP, just give your buddy that address.

Which buddy would that be?

· actions · 2002-Feb-18 7:47 pm ·