3270 DNS Acquistion/assignment

First, my 3270 us one week old, and overall, I love it. The performance is great, and at $799 after rebate, I don't think it can be beat. My question/issue may have more to do with wireless in general, but I hoping the resident gurus can help.
Until last night, I'd boot into Windows, press the wireless button, and within a few seconds, have acquired wireless connectivity with no problem. Last night, for reasons I'm not sure of, the wirelss connected, signal was good to excellent, though I couldn't connect to any internet site (www, pop3, etc). Internal home network connectivity was just fine. I suspected a DNS issue, and sure enough, an ipconfig /all revealed DNS addresses that I couldn't even ping. I assigned two manual DNS addresses to the tcp/ip protocol that correspond to my cable provider's DNS, and bam, that fixed it.
My question: Why should that be necessary. Why is a DNS address being auto-assigned that can't even be reached? And why might this have happend as it did? Recently, I uninstalled AVG A/V, installed McAfee and McAfee firewall. In the confusion, I removed McAfee firewall and just enabled Windows firewall, but I did that prior to configuring my own DNS addresses, and it made no difference. Again, this may be basic networking stuff, but I'm confused. Can anyone shed any light on this for me? Thanks!

Mark

 

1. Zone Alarm. There is no substitute. It takes a while to train it, but it's worth it once you figure out what needs to be let through. It's a pointy-clicky thing to do, so it's not hard...just takes time.

2. Update windows, without fail. Set your autoupdates to download and not install until you tell them to if the auto install disrupts you. XP occasionally has issues with setting your settings (erk bad english) properly. We had some weird DHCP stuff going on in our work network this week, so you may be victim of the same stuff. Don't freak out, this stuff is usually transient and will heal whenever wherever you're getting the addresses from updates, reboots and gets a chance to reset the right settions, or something like that. XP has also had some autoconfiguring issues in the past with the TCP/IP settings as well.

3. While you're booted try to release/renew once you're fully up and see if that helps. Syntax: ipconfig /release then ipconfig /renew. You may have to wait a bit for it to renew if the DHCP server is struggling.

4. if you have access to it or you've configured it yourself, check your DHCP server settings (they may have inadvertently got borked, by themselves or otherwise) and restart your DHCP server (on linux you can directly restart it, on windows you probably have to reboot to make sure it starts up cleanly).

5. try the nice new M$ antispyware...it r0x0rz. Probably because they bought out Giant instead of making their own...and it probably puts its own little spywarez on you too, but they're less malignant than most others.

6. after destroying via tools all the spy/mal ware that might be on your system, pop up task manager and check the process list of stuff that is running. for most stuff running there will be an accompanying svchost.exe. don't sweat that there's a gazillion of them running...it's normal. just go through and check all the others that you don't immediately recognize as being copasetic. if you take the whole name of the executable program that the process is running on and type it into google you will hit some cool reference sites that list all the known processes for microsoft. You can also check them against microsoft too, as they have a comprehensive site that is all nicely hyperlinked and everything...just typ ehte name of the proces sinto their search bar and you'll see. Don't be misled by forum posts...make sure you get at least 3-5 sources that all agree on what your process is that you're currently looking up. htere's a lot of misinformation, deliberate misdirection, howling in forums about ignorant stuff, and just outright crappy bad info on the web. It may take a while, but you'll start to get a feel for what should and shouldn't be there.

If you come up against a process that you cant hit on google by name:
1. find the executable of the process wherever it's sitting on your driver.
2. right click it and check properties.
3. check the version tab in properties...there shoudl be an author or someone taking responsibility for it.
4. if there is an entry, go search on who or whatever was the source of that file and take appropriate actions.

msconfig is neato, but this tool is much, much better. You can use it to find out all the stuff that is starting automagically when you boot your machine, even if you can't find the registry keys or there's nothing in the "startup" folder in your start menu-> programs.

http://www.sysinternals.com/ntw2k/freeware/autoruns.shtml

There's a bunch more fantastic free tools there for you to debug your system. We use some of them at work all the time in our engineering group.

http://www.sysinternals.com/ntw2k/utilities.shtml

Be VERY careful with all of them. They won't do anything just by running them, but they will allow you to get at the guts of your system in excruciating detail...some changes are reversible, some are not...you'll be warned about the ones that aren't. The authors of the tools aren't schmucks and are very, very experienced at what they do...which is why so many people in engineering use their tools...we even bought the pro version of The TCP tools...

If you do not own your DHCP server and this condition persists, ***** to your ISP. If you ahve an internal network, then you're on your own and dependent on the good graces of your ISP for any assistance they might offer. If you're using windows internet connection sharing, for sure restart that system. I think you might be able to get away with disabling and re-enabling the adapter it's configured on in windows XP. 2k was always a crapshoot with networking stuff. God forbid you had your LAN cable unplugged when booting on a corporate network authenticating from a windows PDC. Thank god for Active Directory, LDAP, NIS and other authentication services...

HTH

 

Thanks so much for all of the info (and the time it took you to write it!). I'm familiar with much of what you said, and in fact, did use ipconfig /all to determine the DNS that was being used. I suppose it comes down to the fact that (I do not have my own DNS server) Comcast's DNS (at least the ones that were aquired) were simply down or very slow. I've seen this before, and in fact, had already configured my other systems here with manual DNS servers (about 4 or 5 alternates). Once I did that with the laptop, everything worked fine, and continues to work.

Is it true that all DNS servers are, by their very nature, "open" to access/use? If so, I think I might try to find a list, and ping/tracert overall response times. Maybe there's a utility to do this? It's amazing how much of an impact a good DNS server can make on the overall speed/net experience. BTW, I think your post should be made a "sticky", as it will certainly benefit lots of users. Thanks again.

Mark

 

NP, I type fast and edit little. I try to encourage sharing of good information...this helps grow the community which gives me a bigger base of info to draw from and so on so forth. that also helps me verify what I believe and modify what info I have if something proves out different than it looks.

Comcast does weird **** with their modems. They use this messed up half-bastardized version of dhcp. I have verified by trial and error this because someone I know that had comcast here in oregon (I'm assuming they use a similar infrastructure and similarly featured hardware across the board, for a multitude of reasons I won't go into) was having issues sharing their internet connections.

The situation was that one of the kids was home from college on vacation and wanted to use their own laptop on the broadband. Since they didn't have a switch, hub, router, whatever, because there was normally only one computer in the house they were swapping connections and the thing was borking hard on them. They had been in discussions for a few weeks with comcast regarding this and comcast just told them to reboot the cable modem when they had problems...this sort of made the problem go away...they couldn't figure out how to consistently get the services working properly, even with rebooting the modem.

The problem is this: Comcast's cable modem only issues DCHP info (leases an address, fills in the DNS, etc) upon reboot and from the first attempt at your ssytem to grab an address. After that, it will not take ANY requests for DHCP info from your system. In other words, you have to shut down everything, boot the cable modem, and THEN boot up your computer. Their problem was that they weren't always rebooting their system so it would not acquire all of the proper info or only part of it. For some reason the request your system makes when it's booting is able to be recognized differently by the cable modem than one made after your system is up...I never bothered to drill down into it further after I figured out how to make it come up properly every time. I'm sure with an hour or two of research that the mechanism would become clear, if it took that long at all. If you got lucky and scored a hit on whatever technical documentation exists for the model of modem you're interested in, it could take as little as 10 minutes... But I'm sure it's not obscure or esoteric knowledge...

Anyhow...there were a few periods last year and a lot of them over the couple years before where the internet destabilized a bit in name resolution in general. If you search back a little bit you'll find it coincides with the disturbances at Worldcom, which owns...you guess it...UUNET. There are 6-7 key organizations that if any of them are disrupted, large chunks of the internet will start to get iffy. And it doesn't matter where you are physically located because the internet (and your phone service...) aren't mapped out according to geographic constraints...

http://research.lumeta.com/ches/map/
http://en.wikipedia.org/wiki/List_of_tier_1_internet_service_providers

Not only is UUNET the oldest tier 1 peer, they are also one of the largest exchanges on the planet. If any of the major exchanges on your continent starts having issues, you're hosed and there's not thing 1 you can do about it. An exchange is sort of like a super router...when your domain name activation or change is taking time to propagate on the internet, what's happening is that it's going into whoever is registering and/or hosting your domain name's DNS server, and then depending on how many other DNS it has to bubble up through to get up to the Great Router Table In The Sky and back down through to your ISP's DNS and subsequently your DNS resolver cache on your local system. maybe a secondary or tertiary level DNS that something in your food chain points at went flakey for a bit...the more stuff that depends on a particular server, the more closely it's usually monitored and subsequently more quickly resolved.

With the impending bankruptcy of Worldcom, stuff went to hell at the commpany, and therefore it's services started flaking out HARD for a good period of time...

 

apologies for the double post (no edit option available...)

No, all DNS aren't necessarily open, but most are. It takes extra work to configure them such and unless they're being flooded it's usually not a hindrance. The case that I've experienced where things were bad was when my web hosting company was using one of the shared/virtual host servers for double duty as a DNS. Large file transfers would cause timeouts in domain name resolution for customers...even when users were fully within their rights to do so. They remedied that in a hurry...maybe they didn't think that the requests were going to be affected as adversely by doing things that way. Possibly they were trying to save money on avoiding buying dedicated DNS servers because the business was just starting up...maybe a little of both.

Anyhow...you should be able to use most DNS that you can find the address or name of, unless someone's watching the logs and blocking those IP that aren't their customers. I would do that on general principles since my customers woul be the ones supporting the service and therefore deserve to have a DNS all to themselves.

 

Thanks again to both of you for the plethora of good info. I encountered problems again last night, even with my manually entered (known functional) DNS numbers. The Averatec aquires the WLAN network, signal shows very good to excellent, and an IPCONFIG /ALL showed an IP and DNS number consistent with those of my working desktop systems. Still, no connectivity to the internet, and I noticed that the "Internet Gateway" connection never starts/shows among the connections. Feeling I had nothing to lose, I upgraded the WLAN driver to the most current Ralink 11g-RT2500 driver. It created a new wireless connection, and as expected, with auto IP and DNS assingment. So far, it's working. I'm puzzled though. I've got a TiVo on the wireless network, and that thing never seems to fail to grab and maintain a connection. The Averatec though, seems somewhat finnicky. I'm not sure what to think at this point. It doesn't seem that it's an issue reported as being a "bug", but I've still got about 6 days to return this thing if necessary. Again though, I'm not sure it's the notebook.

Mark

 

I have a 3250 - about four weeks now - and it's onboard wireless also uses the RaLink RT2500. It is not as sensitive when I compare it to other laptops under the same conditions. In fact I've just about abandoned it and am using a Belkin USB wireless adapter. It is way, way better than the onboard wireless.

Over the weekend I was in a hotspot area where the onboard wireless would not see the access point and the Belkin did so with ease.

Others have reported in the Averatec forum that they also find the onboard wireless that uses the RT2500 is not as good as they would expect or had hoped.

 

Thanks. It's been about 24 hours since I updated the driver, and about 5 power up/down cycles, and so far, it's worked very well. It seems to make the connection 1st time, every time, and maintain it. I won't feel certain it has *really* made a difference until a few more days pass, but I am optimistic. I may end up doing as you suggest, and go with a USB adapter. I use a Linksys WUSB12 with my TiVo, so if necessary, maybe I'll do the same with this. Hopefully, that won't be necessary though.

Mark

 

I'm having no issues whatsoever with the broadcom in the 3220 and the ralink in the 3270. They both work just fine. I'm in the process of replacing my POS Cheapass Airlink AP because I hve to reboot it like every other day...with a linksys wrt54g of course. There's plenty of boosty stuff you can do with the linksys. It's super hackable and you can load up soft hacks to test it out, no problem. Just cycle the power on the AP and everything goes away...many of them load in resident memory instead of writing to the flash, so no worries.

Make sure you are updating your XP system religeously, especially if you have SP2. Many wireless features that are very happenin in SP2 weren't stable when it first came out, especially if you use bluetooth adapters with your system. They've fixed most of it now, for the most part everything seems to work okay.

Set your updates to download and not install. Then they'll just download ikn the background whenever you're on and pop up a notifyer balloon when they're ready to go.

There's also a lot of transient effects you can get with wireless...especially if you can't see the AP w/ your eyes. Unless you got a direct LOS (line of sight) with A or G systems, you can get massive attenuation and multipath going on, especially if you're trying to hook up to a cheap AP which may be weak as well as not having diversity...

If it ain't got two antennas, it ain't got diversity. Diversity helps eliminate multipath distortion of signals which can clobber your data rate even if you have a strong signal.