1.2 The Site
See more about how the site is run: /aboutdsl
We really squeeze every ounce out of our hardware resources here. The site started out on an old Dell 2300 tower with two PII processors running at 450mhz and 1gig of memory, plus six 9gig SCSI LVD 10k RPM drives and two intel/etherpro 10/100 ethernet cards.
This was built over a year ago and, apart from a memory upgrade, has run like a champ since. It stands now as our firewall and miscellaneous random script machine.
We soon added a bunch more machines, several Intel 2150s rackmounts, with 600mhz to 1ghz PIIIs, 1gig-2gigs of memory and 18gig SCSI LVD 10k RPM drives. We also have several second-hand 2U high VA Linux servers of similar configuration. Our newest performer is a 1-unit high Dell with 4gigs of memory and 2x1ghz PIII CPUs. Currently, I think we have about 18 or 20 CPUs (9 or 10 servers), if you count them all.
Most CPUs are located in New Jersey, at nac.net. We last saw/touched the machines in November 1999. A few more are at UUnet webhosting.
All the machines started as Redhat 6.x, but with everything stripped out and the critical parts (Apache, modperl, MYSQL) recompiled.
Our current connection to the data-center switch at nac.net is 100Mbit.
The site is maintained over DSL, cable modems and SSH2.
Is this a lot of hardware? Doesn't sound like much! It isn't a lot by any standard. We probably have the highest dynamic page/cpu ratio of any site on the web. Any web business would be talking Sun Enterprise servers and large Oracle databases for our traffic.
Why not use PHP? PHP is designed to generate web pages. Perl and associated Perl modules are designed to do anything. So, since we are required to do more than just web pages, Perl is a better choice for us.
Why not use FreeBSD? It is claimed that FreeBSD behaves better at high load than Linux. We should have used it over RedHat. Unfortunately, FreeBSD SMP support was lacking at the time the decisions were made, so we are where we are -- and reasonably happy as well. Sometimes upgrading to new kernels is a lucky dip, but a stable configuration stays stable for months or years.
Our forum software is custom written and is tightly integrated into the site. There is no easy way to extract just the forum software and make it available to others.
The server load indicator (seen at the top right of the page) is created from monitoring pages shown per second. It is calculated dynamically from the last few minutes of activity on the servers. Each block that is lit indicates 1/6th of what we consider to be maximum efficient load.
The figure in brackets indicates how many pages per minute we are currently printing.
If the 6 lit blocks are replaced by the word "overload," our server may not produce all pages correctly, or may have some difficulty. In that case, please visit later when the problem has been corrected.
The web part of DSLreports.com comprises several servers located at a data center in New Jersey (nac.net).
Data centers usually have multiple connections (peerings) to the Internet.
From time to time, problems (failures, network attacks, reconfiguration, etc) at the data center can cause browsing the site to become slow, or even stop completely. In an effort to detect this, we continually monitor our own connectivity to the Internet for any temporary packet loss, so we can show this statistic in the form of an icon on the home page.
Feedback received on this FAQ entry:
I just tried to access a forum a few minutes ago, and I got this error:
"503 Request temporarily denied: too many requests arriving from your IP address. See this page for more information:"
On that page, you see this info:
About: request denied, error 503One solution to this problem is not to check "cache unlisted pages" if you are using AdShield.
A second cause is clicking topics too rapidly, as in your "favorite forums" page when trying to catch up. If this is happening to you, try using the "clear all" button at the top of the page to catch up with all your forums.
If you or someone else is truly in desperate straits, and you can clearly establish this through verifiable evidence (other than your word), you may contact a site moderator and discuss your situation with him/her. That moderator may wish to discuss it with others before a decision is made. Otherwise, we cannot allow posts that contain such solicitations, including those in posting sigs, to appear in any area of the site.
•You never respond to trolls or flame other users.
•Your posts stick to the forum topic.
•You never post for the sake of posting.
•You remain reasonable when things get heated.
•You know what it means to "agree to disagree."
•You're polite, friendly and enjoy interacting with other people.
•You ALWAYS say thank you.
The Bad Way:
•Your posts are frequently off-topic and your questions are unrelated or repeated.
•You post "My Provider Sucks! Don't get them!" without saying WHY.
•You like to see your name on the screen, so you
•Re-ask your question ... after only an hour ...
•Start a new thread to answer a question ...
•You ask the same question in multiple forums.
•You re-open topics closed by moderation.
•You NEVER say thank you.
from a post by Wheelert
When an announcement is prepared and activated, those who are affected will see it at some point while browsing the site.
Use the "OK I got it" link to clear the screen. This marks it as having been viewed.
As soon as the announcement page interrupts a URL and is shown, it is marked as having being seen. There is only a 1 in 20 chance that announcements are shown on any page load, so not everyone will see them instantly.
This feature will be used sparingly so that it does not interrupt site users except on rare occasions.
If you are creating a topic that is probably NOT one for the front page, such as personal events (births, deaths, sickness, marriage, etc.), you should place [OT] or OT: in front of the thread title. This prevents it from being picked up and included on the front page.
If your topic has unintentionally appeared on the front page, and you don't think it should be there, you can ask a moderator to edit the title so it includes one of the labels above. This will cause it to be removed from the front page display.