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Redbook

join:2000-12-23
united state

Intermittently can't find server

My wife has Earthlink DSL with a ZyXel Prestige 600 series modem where she works. For the last week she gets a "Can't find server" intermittently when she clicks on a link. She may have to click the link 3 or 4 times before a site loads. She says the modem lights are the same whether a site loads or not. I thought I'd post here before going through the pain of calling Earthlink support. Her computer is Windows 7 - 64 bit.

Thanks,
Len



Doctor Olds
I Need A Remedy For What's Ailing Me.
Premium,VIP
join:2001-04-19
1970 442 W30
kudos:18

Have her try different DNS IPs by setting them either in the PC or in the Modem if it is in Router Mode. If she needs step by step instructions reply back with the actual Model Number from the bottom label on the ZyXEL.

Optional DNS info here:

»EarthLink DSL FAQ »What are the DNS Opt Out Servers for the Redirecting Earthlink DNS Problem?
--
What’s the point of owning a supercar if you can’t scare yourself stupid from time to time?



Redbook

join:2000-12-23
united state

Thanks very much, I'll let you know the exact model number of the modem later in the day. How do you know if the modem is in router mode?

Len



Redbook

join:2000-12-23
united state
reply to Doctor Olds

So here's the ZyXEL model number: 645M-UHP, adsl.

Thanks Doctor Olds


rhendrix9

join:2003-10-05
Marietta, GA

1 edit
reply to Redbook


If you find a solution, please let me know.



Doctor Olds
I Need A Remedy For What's Ailing Me.
Premium,VIP
join:2001-04-19
1970 442 W30
kudos:18

1 edit
reply to Redbook

It is in Router Mode when the Username and Password for PPPoE are set in the UHP Modem. The UHP Modem IP is »172.16.0.254

»EarthLink DSL FAQ »What is a UHP modem?

and

»EarthLink DSL FAQ »How to Specify DNS Information in the EarthLink UHP ADSL Modem

Those should have the info you need.

Also I personally use 4.2.2.2 and 4.2.2.4 (alternate use of 4.2.2.1 and 4.2.2.3 is acceptable).

You want the fastest response time (pick the best two IPs) and you can test it by using this GRC.com DNS utility.

Domain Name Speed Benchmark
»www.grc.com/dns/benchmark.htm

Note: After changing DNS in the Router/Modem, renew the IP info in Windows to get the new DNS IPs into the PC settings so the system can now use them.

Release and Renew an IP address in Windows 7
»wiki.csuchico.edu/confluence/dis···indows+7

HTH
--
What’s the point of owning a supercar if you can’t scare yourself stupid from time to time?



Redbook

join:2000-12-23
united state

Thanks for the reply. Before I received it, I contacted Earthlink support and ended up talking to several incompetents then on to a supervisor who had me change the DNS server within Windows (from automatic) to 207.69.188.185 and 207.69.188.186. This seemed to solve the problem but I ran the DNS Benchmark test anyways. Here is the result:

207.69.188.185
207.69.188.186

DNS Benchmark Conclusions & Recommendations

What the results you have just obtained mean to YOU

The results summary, conclusions, and recommendations from your most recent run of this DNS benchmark are provided below. Please carefully consider the implications of making any changes to your system's current configuration before doing so.

Only the built-in default resolvers were benchmarked.
Please consider taking the time to create a custom resolver list.
This is a reminder about the tremendous benefits to be gained from benchmarking the "Top 50" resolvers that are found for you by the Benchmark's custom resolver list builder. When you have time, don't forget to give that a try. The results will astound you! You can find the option to do this on either the application's System Menu (Alt-Spacebar) or on the Add/Remove nameservers dialog on the Nameservers page.

System has multiple redundant nameservers configured.
This system is currently configured to use 2 separate nameservers for DNS name resolution. This is in keeping with recommended best practice (of having at least two different nameservers) so that the temporary failure of any single nameserver will not prevent all DNS name resolution.

All system nameservers are alive & replying to queries.
All of this system's 2 nameservers are working and replying to queries. This is terrific because if the system's primary nameserver were to become overloaded or unavailable, even briefly, one or more backup nameservers are standing by ready to supply DNS lookup services.

System nameservers are NOT ordered for best performance!
Windows uses DNS servers in the order they are listed under the network adapter's properties, or when obtained automatically from an ISP, in the order provided by the ISP. Windows will fall back to using the second, third, and other nameservers only when the first listed nameserver fails to respond. So if the first nameserver happened to be very slow, but working, everything would be slowed down. Consequently, the order of nameserver listing should match their order of decreasing performance . . . but this is not how this system is currently configured:

In this most recent test, a faster nameserver
was listed in order after a slower one.

The following table shows the order of this system's usage of its configured nameservers versus their comparative performance ranking:

Usage Order Nameserver IP Speed Rank
----------- --------------- ----------
1 207. 69.188.185 2 unreliable
2 207. 69.188.186 1 unreliable

With at least 95% Certainty. . .
You have received this "red flagged" message because there was enough of a statistically significant difference between the benchmarked nameserver performance for this program to make a highly confident determination that improvement is possible by "re-ordering" this system's nameservers.

Recommended Actions:

• Before you make any changes: Even though there appears to be a statistically significant difference in the measured performance of these nameservers, you should re-run the benchmark - perhaps at different times of the day, and even on different days - to verify that the current configuration consistently produces this "misordering" note (the slower nameserver might just be having a bad day.) If the trouble persists, then changing the nameserver order will definitely improve your system's Internet performance!

System nameservers are SLOWER than 29 public alternatives!
This benchmark found 29 publicly available DNS nameservers that are reliably faster than the slowest nameserver currently being used by this system. If you were to adjust your system's configuration to use the faster of these nameservers instead of what it is currently using, your DNS lookup performance, and all use of the Internet, would be improved.

Recommended Actions:

• With at least 95% certainty: Based upon a statistical analysis of the spread in timing value samples received during the benchmark, there is at least a 95% certainty that the performance conclusions stated above are correct. But even so, since changing DNS nameservers requires thought and effort, it's something you want to be sure about. Therefore, since these results represent a single snapshot in time, you may wish to confirm that the faster alternative nameservers are consistently faster than your system's currently configured nameservers, and that those public alternatives don't have any negative characteristics such as being colored orange to signify that they redirect mistaken URLs to an advertising-laden search page rather than returning an error (which will be a concern to some users).

• You may also wish to check the relative performance at different times of day to make sure that the performance improvement over your system's current nameservers is reliable throughout the day.

• And you may wish to make sure that the alternative nameservers are enough faster than what you are currently using for the improvement to be worth changing away from what you're currently using. (This test is only saying that it's 95% sure they are any amount faster.)

One or more system nameservers is NOT 100% reliable!
DNS reliability is extremely important, since lookup requests that are dropped and ignored by nameservers cause significant delays in Internet access while the querying system waits for a reply. The system is then finally forced to reissue the query to the same or to backup nameservers. While your system is patiently waiting for a reply, you are impatiently waiting to get on with your Internet access.

During this benchmark test, the nameservers being tested did not reply to some of the DNS queries they were sent.

So the question now is: Did the benchmark discover alternative nameservers having superior performance and reliability to which you could switch in order to obtain more performance and reliability?

Important Note:

• Incorrect warnings of low reliability nameservers can arise if (1) DNS benchmarking is being performed while the local network is busy performing other work such as file downloading, or (2) the benchmark is running over a wireless (WiFi) link with low signal strength or high interference. Please try to minimize any other local network activity while the benchmark is running, and use a wired (not wireless) LAN connection if possible.

Recommended Actions:

• Before you make any changes, you should probably run the benchmark a few more times at differing times of day to make sure that the troubling reliability is an ongoing problem and not just a brief occurrence.

• You may also wish to consult the "Tabular Data" page which summarizes all benchmark results in numeric tables. The numbers make it easier to see exactly how unreliable your system's nameservers are compared with the available alternatives. (And also how the alternatives' performance compares.)

All of this system nameservers return errors.
This is a GOOD thing! Some DNS providers, such as OpenDNS and even the Earthlink, Roadrunner and Comcast ISPs, redirect incorrectly entered URLs to their own advertising-laden marketing-driven interception page instead of simply returning an error to the web browser. But this system's nameservers are returning errors when asked to lookup non-existent domain names.

System nameservers are replying to all query types.
During the development of this DNS Benchmark we discovered that the routers used by some pre-release testers were not returning results for the benchmark's Uncached and/or Dotcom testing queries. Even though these queries are admittedly unusual, they are completely valid. So the only conclusion was that those few routers were inherently defective. The good news here is that your nameservers are replying to these unusual but valid queries.

____________________________________________________________________

REMEMBER TO CHECK SPOOFABILITY !!
Whether you make any changes to your nameservers or not, but
especially if you do, be sure to verify the security of your final DNS
resolver set by using GRC's free "DNS Spoofability" testing service!

»www.GRC.com/dns/dns.htm
_______________________________________________________________________________________________________________________

If you require assistance . . .

If you require assistance with the implementation any of the suggested changes to your system's DNS configuration, several sources of help are available:

• For help with the operation and use of this DNS Benchmark program, please reference the extensive DNS Benchmark pages at the GRC website:

»www.GRC.com/dns/benchmark.htm

• For help with any of the specific conclusions or recommendations above, please see the DNS Benchmark FAQ (Frequently Asked Questions) page:

»www.GRC.com/dns/benchmark-faq.htm

• Knowledge of the DNS domain name system is widespread among those in public technical Internet forums. You will very likely be able to obtain answers to any specific questions you may have by asking knowledgeable inhabitants of online communities.

• GRC maintains and operates a comprehensive online "newsgroup" community and has a specific newsgroup - grc.dns - dedicated to the discussion of DNS issues including this DNS benchmark program (where it was developed) and GRC's online DNS Spoofability testing service. Please see the following web page for help with joining and participating in GRC's terrific newsgroups:

»www.GRC.com/discussions.htm

GRC's technical support services are limited to the support of licensees of our commercial software products and do not extend to the support of our freely available software or online services. Please do not write to us (GRC / Gibson Research Corporation) for assistance in connection with this freeware utility.

You will find that ample help is freely available
within the Internet community. Thank you!

- Steve Gibson

Please Note: This program is Copyright (c) 2010 by Gibson Research Corporation -- ALL RIGHTS RESERVED. This program is FREEWARE. Although it may not be altered in any way, it MAY BE FREELY COPIED AND DISTRIBUTED onto and through any and all computer media in ANY form or fashion. You are hereby granted the right to do so.
• • •

Docs DNS Settings Benchmark:

DNS Benchmark Conclusions & Recommendations

What the results you have just obtained mean to YOU

The results summary, conclusions, and recommendations from your most recent run of this DNS benchmark are provided below. Please carefully consider the implications of making any changes to your system's current configuration before doing so.

System has multiple redundant nameservers configured.
This system is currently configured to use 2 separate nameservers for DNS name resolution. This is in keeping with recommended best practice (of having at least two different nameservers) so that the temporary failure of any single nameserver will not prevent all DNS name resolution.

All system nameservers are alive & replying to queries.
All of this system's 2 nameservers are working and replying to queries. This is terrific because if the system's primary nameserver were to become overloaded or unavailable, even briefly, one or more backup nameservers are standing by ready to supply DNS lookup services.

System's nameservers are probably optimally ordered.
Windows uses DNS servers in the order they are listed under the network adapter's properties, or when obtained automatically from an ISP, in the order provided by the ISP. Windows will fall back to using the second, third, and other nameservers only when the first listed nameserver fails to respond. So if the first nameserver happened to be very slow, but working, everything would be slowed down. Consequently, the order of nameserver listing should match their order of decreasing performance . . . which is probably how this system is currently configured:

Usage Order Nameserver IP Speed Rank
----------- --------------- ----------
1 4. 2. 2. 2 2
2 4. 2. 2. 4 1

Why only "probably" ?
Only "probably" because there wasn't enough of a statistically significant difference between their timings to be able to make any claims with at least 95% confidence. Here are the details:
When this benchmark is allowed to finish, it will have collected approximately one hundred and fifty (150) DNS performance samples from each nameserver being tested. Although this is sufficient to generate a good average performance estimate, if the collection of sampled values are too widely spread apart (in other words, not a lot of agreement among samples), it is impossible to know with "statistical certainty" (to be 95% sure) how individual nameservers compare to each other.
Therefore, even if the ranking shown above appears to be out of order, the differences are not statistically significant, and you should not be concerned. If you were to re-run the benchmark you might get a different outcome. This benchmark conclusion page will inform you when a problem exists that is statistically significant, and will then advise you that your DNS nameserver settings should be changed. But that is not the case with the benchmark results that were just obtained.

System nameservers are faster than ALL public alternatives.
All of the DNS resolvers your system is using are responding faster than any of the 100% reliable publicly available alternative DNS nameservers this benchmark utility just tested. Therefore, there would be no performance benefit from replacing any of this system's current nameservers with any of those publicly available alternatives. However, this best performance appraisal assumes that this system's nameservers are 100% reliable. See the next item below for an appraisal of your nameservers' reliability.

Note: If there appeared to be one or more faster public alternative nameservers, there was enough uncertainty created by the spread of benchmark timing results that it was not possible to be at least 95% confident that any of those faster-seeming nameservers really were reliably faster than the nameservers this system is currently using. So it made no sense to alarm you about the need to change things when there was insufficient evidence.

This system's nameservers are 100% reliable.
DNS reliability is extremely important, since lookup requests that are dropped and ignored by nameservers cause significant delays in Internet access while the querying system waits for a reply. The system is then finally forced to reissue the query to the same or to backup nameservers. While your system is patiently waiting for a reply, you are impatiently waiting to get on with your Internet access.

During this benchmark test, all of the system's nameservers tested returned a reply for every request sent. It doesn't get any better than that. Very nice.

All of this system nameservers return errors.
This is a GOOD thing! Some DNS providers, such as OpenDNS and even the Earthlink, Roadrunner and Comcast ISPs, redirect incorrectly entered URLs to their own advertising-laden marketing-driven interception page instead of simply returning an error to the web browser. But this system's nameservers are returning errors when asked to lookup non-existent domain names.

System nameservers are replying to all query types.
During the development of this DNS Benchmark we discovered that the routers used by some pre-release testers were not returning results for the benchmark's Uncached and/or Dotcom testing queries. Even though these queries are admittedly unusual, they are completely valid. So the only conclusion was that those few routers were inherently defective. The good news here is that your nameservers are replying to these unusual but valid queries.

System is using one or more Level 3 nameservers.
Just a note: During the development testing of this benchmark, many of our testers who had been using Level 3's nameservers (4.2.2.1 through 4.2.2.6) discovered that they were less reliable - especially over the weekends - than they previously knew. As a result, they demoted those nameservers in their system's nameserver list so that they were used only as last resort backups.

Recommended Actions:

• Since you are using Level 3's servers in some capacity, you might want to keep a close watch on them for a while by running this benchmark from time to time - especially over the weekends - to check their performance and reliability and verify that you're happy with the role they are playing for you.

Then I changed (within Windows) to the ones that you recommended (4.2.2.2 and 4.2.2.4). The benchmark test passed all criteria.

So many thanks again,
Len


Redbook

join:2000-12-23
united state
reply to rhendrix9

Check out my latest reply to Doc. If you're having the same intermittent problem with EL DSL, here's what I did:
control panel>network connections>right click on your adapter>properties>highlight Internet Protocol>properties>click the radio button for "use the following DNS server addresses>type in 4.2.2.2 for the first one then 4.2.2.4 for the second>ok's. This is assuming that you currently have it set to automatically find the DNS server and it's just not working right.

If this doesn't work post the problem, I know a bit about computers but very little in this area. Doc seems to be the expert, so I suggest working with him and if you can avoid it, don't deal with Earthlink support unless you want to pull your hair out.

Len



Doctor Olds
I Need A Remedy For What's Ailing Me.
Premium,VIP
join:2001-04-19
1970 442 W30
kudos:18
reply to Redbook

said by Redbook:

Thanks for the reply. Before I received it, I contacted Earthlink support and ended up talking to several incompetents then on to a supervisor who had me change the DNS server within Windows (from automatic) to 207.69.188.185 and 207.69.188.186. This seemed to solve the problem but I ran the DNS Benchmark test anyways.

[snip]

Then I changed (within Windows) to the ones that you recommended (4.2.2.2 and 4.2.2.4). The benchmark test passed all criteria.

So many thanks again,
Len

You are most Welcome. Glad that I could help when I can. Have your spouse keep a lookout for the old behavior and if it does not return then you have fixed it by replacing flakey DNS resolution with competent DNS resolution. It is amazing what difference that can make for a end users experience.

You also might have her run several speed tests at the two sites linked below to make sure that her speeds are stable and where they should be depending on what service level she has purchased.

»www.speedtest.net/

»www.speakeasy.net/speedtest/

Regards,

Doctor Olds
--
What’s the point of owning a supercar if you can’t scare yourself stupid from time to time?

rhendrix9

join:2003-10-05
Marietta, GA
reply to Redbook

I have the Zyxel 660-R-ENLK and a wrt54gs set in PPPoE mode.
I have a house full of pc's, laptops,tablets,cell phones.... If I set the DNS server for my pc, it is not going to help any other device in the house, right?

Should the Zyxel be in PPPoE mode instead of what ever mode it's in?


rhendrix9

join:2003-10-05
Marietta, GA
reply to Redbook

What operating system are you using? I have not found a place to set DNS yet.

I'm widows 7



Doctor Olds
I Need A Remedy For What's Ailing Me.
Premium,VIP
join:2001-04-19
1970 442 W30
kudos:18
reply to rhendrix9

said by rhendrix9:

I have the Zyxel 660-R-ENLK and a wrt54gs set in PPPoE mode.
I have a house full of pc's, laptops,tablets,cell phones.... If I set the DNS server for my pc, it is not going to help any other device in the house, right?

Correct, you should not set Static DNS IPs in a PC when it is just one of many devices, let the Router in charge of the LAN handle DNS settings and have all devices set for Automatic DHCP and DNS. Now if you only have one PC and one Modem/Router you can then set either one, but the Router is preferred so a PC stays set to Automatic.

said by rhendrix9:

Should the Zyxel be in PPPoE mode instead of what ever mode it's in?

Set DNS in the device that handles PPPoE and DHCP. I'd assume you have the ZyXEL setup in bridge mode. Correct? That's recommended when you have a second Router. Let it handle everything so you don't have Doubled-NAT/NAPT from having multiple Routers translating data before it reaches your devices.

All devices should be set for Automatic DHCP and the Router gets setup with custom DNS IPs so it will update each device automatically as long as they are not setup with Static IP and DNS data.
--
What’s the point of owning a supercar if you can’t scare yourself stupid from time to time?


Doctor Olds
I Need A Remedy For What's Ailing Me.
Premium,VIP
join:2001-04-19
1970 442 W30
kudos:18
reply to rhendrix9

said by rhendrix9:

What operating system are you using? I have not found a place to set DNS yet.

I'm widows 7

In your Router when you have more than one PC. Even if you only have one PC and no other IP Devices it is better to set the Static DNS in the Router.



--
What’s the point of owning a supercar if you can’t scare yourself stupid from time to time?

rhendrix9

join:2003-10-05
Marietta, GA
reply to Doctor Olds

setting it in the router makes sense

thanks


rhendrix9

join:2003-10-05
Marietta, GA
reply to Doctor Olds

i set everything except automatic - DHCP

my first speakeasy was 0.72/0.31

exasperating



Doctor Olds
I Need A Remedy For What's Ailing Me.
Premium,VIP
join:2001-04-19
1970 442 W30
kudos:18

Correct, your unit should be PPPoE.

Note, Changing DNS IP doesn't fix speed or line quality issues, it fixes "Can't find server" errors and how quickly the server pages are found. Loading times/speeds are unchanged. You need to perform basic trouble shooting, make sure you don't have a bad Ethernet cable or missing/bad DSL Filter and test out at the NID and see what your DSL line stats look like.

»Re: [Speed Problem] Earthlink DSL speed slows to a crawl when ad
--
What’s the point of owning a supercar if you can’t scare yourself stupid from time to time?