OT RE: load balancing on apache by IP CHAINING
I don't know how many of you read SysAdmin (http://www.samag.com), but there is an interesting article on running IPChains at runlevel 0. --Joe Breeden What to do... if you get a phone call from Mars: Speak slowly and be sure to enunciate your words properly. Limit your vocabulary to simple words. Try to determine if you are speaking to someone in a leadership capacity, or an ordinary citizen. if he, she or it doesn't speak English? Hang up. There's no sense in trying to learn Martian over the phone. If your Martian really had something important to say to you, he, she or it would have taken the trouble to learn the language before calling. if you get a phone call from Jupiter? Explain to your caller, politely but firmly, that being from Jupiter, he, she or it is not life as we know it. Try to terminate the conversation as soon as possible. It will not profit you, and the charges may have been reversed. -Original Message- From: David Young [mailto:[EMAIL PROTECTED]] Sent: Sunday, December 16, 2001 10:45 AM To: [EMAIL PROTECTED] Subject: Re: load balancing on apache by IP CHAINING Servlet chaining is what the Java web server will do, and it has nothing to do with load balancing (that I can think of). ipchains is the command to enable firewall/packet filter/packet masquerading capability in linux. I would suppose that it can be used to round-robin requests or something, but I don't know how to set that up. From: Medi Montaseri [EMAIL PROTECTED] Date: Sat, 15 Dec 2001 20:57:19 -0800 (PST) To: Anand R [EMAIL PROTECTED] Cc: [EMAIL PROTECTED], [EMAIL PROTECTED] Subject: Re: load balancing on apache by IP CHAINING I'm confused'IP chainging' as the name says is at the IP (or Network) layer, what does that have to do with Apache or any HTTP server at the application level. I think any such IP based load balancing technologies are inherently unaware of the total system issues and are simply making a jugdment based on the IP level or perhaps a specific protocol on top of IP to route the next packet (or next session). Having said that a Perl HTTP would/could benefit from it just as well... On Sat, 15 Dec 2001, Anand R wrote: IP chaining can be done in Java Webserver, How to do it in Apache Webserver. Please let the Ring know this, Thanks in advance, Regards, Anand - Original Message - From: Derek Jones To: Hemant Singh ; [EMAIL PROTECTED] Cc: Derek G Jones Sent: Friday, December 14, 2001 7:29 PM Subject: RE: load balancing on apache Hi all, You can do load balancing using ipchains as well. Can't remember the program name offhand, but if I have time I'll look it up and let the list know. Only works if your servers are Linux of course. Kind regards Derek. -- Derek Jones 1051, Bollinger Road, Tel:717 359 8817 Littlestown, Mobile: 717 977 4556PA, 17340, USA Email: [EMAIL PROTECTED] AIM: scunacc -- -- --- Medi Montaseri [EMAIL PROTECTED] Unix Distributed Systems Engineer HTTP://www.CyberShell.com CyberShell Engineering -- ---
Re: load balancing on apache by IP CHAINING
Servlet chaining is what the Java web server will do, and it has nothing to do with load balancing (that I can think of). ipchains is the command to enable firewall/packet filter/packet masquerading capability in linux. I would suppose that it can be used to round-robin requests or something, but I don't know how to set that up. From: Medi Montaseri [EMAIL PROTECTED] Date: Sat, 15 Dec 2001 20:57:19 -0800 (PST) To: Anand R [EMAIL PROTECTED] Cc: [EMAIL PROTECTED], [EMAIL PROTECTED] Subject: Re: load balancing on apache by IP CHAINING I'm confused'IP chainging' as the name says is at the IP (or Network) layer, what does that have to do with Apache or any HTTP server at the application level. I think any such IP based load balancing technologies are inherently unaware of the total system issues and are simply making a jugdment based on the IP level or perhaps a specific protocol on top of IP to route the next packet (or next session). Having said that a Perl HTTP would/could benefit from it just as well... On Sat, 15 Dec 2001, Anand R wrote: IP chaining can be done in Java Webserver, How to do it in Apache Webserver. Please let the Ring know this, Thanks in advance, Regards, Anand - Original Message - From: Derek Jones To: Hemant Singh ; [EMAIL PROTECTED] Cc: Derek G Jones Sent: Friday, December 14, 2001 7:29 PM Subject: RE: load balancing on apache Hi all, You can do load balancing using ipchains as well. Can't remember the program name offhand, but if I have time I'll look it up and let the list know. Only works if your servers are Linux of course. Kind regards Derek. -- Derek Jones 1051, Bollinger Road, Tel:717 359 8817 Littlestown, Mobile: 717 977 4556PA, 17340, USA Email: [EMAIL PROTECTED] AIM: scunacc -- - Medi Montaseri [EMAIL PROTECTED] Unix Distributed Systems EngineerHTTP://www.CyberShell.com CyberShell Engineering -
Re: load balancing on apache by IP CHAINING
I'm confused'IP chainging' as the name says is at the IP (or Network) layer, what does that have to do with Apache or any HTTP server at the application level. I think any such IP based load balancing technologies are inherently unaware of the total system issues and are simply making a jugdment based on the IP level or perhaps a specific protocol on top of IP to route the next packet (or next session). Having said that a Perl HTTP would/could benefit from it just as well... On Sat, 15 Dec 2001, Anand R wrote: IP chaining can be done in Java Webserver, How to do it in Apache Webserver. Please let the Ring know this, Thanks in advance, Regards, Anand - Original Message - From: Derek Jones To: Hemant Singh ; [EMAIL PROTECTED] Cc: Derek G Jones Sent: Friday, December 14, 2001 7:29 PM Subject: RE: load balancing on apache Hi all, You can do load balancing using ipchains as well. Can't remember the program name offhand, but if I have time I'll look it up and let the list know. Only works if your servers are Linux of course. Kind regards Derek. -- Derek Jones 1051, Bollinger Road, Tel:717 359 8817 Littlestown, Mobile: 717 977 4556PA, 17340, USA Email: [EMAIL PROTECTED] AIM: scunacc -- - Medi Montaseri [EMAIL PROTECTED] Unix Distributed Systems EngineerHTTP://www.CyberShell.com CyberShell Engineering -
Re: load balancing on apache
Hi Hemant Singh, A round-robin dns server would be easiest. There's no true load balancing this way though. Regards, John Hoffman - Original Message - From: Hemant Singh Sent: Friday, December 14, 2001 1:29 AM To: [EMAIL PROTECTED] Subject: load balancing on apache Hi All I am planning to host an application and its size is going to be big one , so expect the concurrent number of connection s to be around 2200.To combat the same , want to perform load sharing on 3-4 servers.So the ide is to put one machine on external IP and this machine , after receiving the requests would forward them to any of the other three machines having the application deployed and running on the same environment.Pls suggest how can i achieve this on apache. Thanks in advance HemantGet more from the Web. FREE MSN Explorer download : http://explorer.msn.com
Re: load balancing on apache
On Fri, 14 Dec 2001, Hemant Singh wrote:
Pls suggest how can i achieve this on apache.
mod_backhand may be able to help you out here with proper pass it on
type load balancing. If you use it with wackamole you might not even need
the front machine.
http://www.backhand.org/
Haven't used it myself, but people I know say good things about their
experiences with it.
--
s'' Mark Fowler London.pm Bath.pm
http://www.twoshortplanks.com/ [EMAIL PROTECTED]
';use Term'Cap;$t=Tgetent Term'Cap{};print$t-Tputs(cl);for$w(split/ +/
){for(0..30){$|=print$t-Tgoto(cm,$_,$y). $w;select$k,$k,$k,.03}$y+=2}
Re: load balancing on apache
Hemant Singh [EMAIL PROTECTED] writes: Hi All I am planning to host an application and its size is going to be big one , so expect the concurrent number of connection s to be around 2200.To combat the same , want to perform load sharing on 3-4 servers.So the ide is to put one machine on external IP and this machine , after receiving the requests would forward them to any of the other three machines having the application deployed and running on the same environment.Pls suggest how can i achieve this on apache. Depends how much session persistence you're keeping on the middle tier. You can do things smarter than pure round robin with a few mod_rewrite rules on the front. -- David Hodgkinson, Wizard for Hirehttp://www.davehodgkinson.com Editor-in-chief, The Highway Star http://www.deep-purple.com Deep Purple Family Tree news http://www.slashrock.com Interim Technical Director, Web Architecture Consultant for hire
Re: load balancing on apache
-- Hemant Singh [EMAIL PROTECTED] Hi All I am planning to host an application and its size is going to be big one , so expect the concurrent number of connection s to be around 2200.To combat the same , want to perform load sharing on 3-4 servers.So the ide is to put one machine on external IP and this machine , after receiving the requests would forward them to any of the other three machines having the application deployed and running on the same environment.Pls suggest how can i achieve this on apache. Randal Schwartz had a good article on this about a year ago. You can use the re-write phase to balance the load w/in Apache if you want to. Alternatives include round- robin DNS and separate load balancing software. -- Steven Lembark 2930 W. Palmer Workhorse Computing Chicago, IL 60647 +1 800 762 1582
Re: load balancing on apache
I am planning to host an application and its size is going to be big one , so expect the concurrent number of connection s to be around 2200. To combat the same , want to perform load sharing on 3-4 servers. If you really expect 2200 concurrent connections, you should buy dedicated load-balancing hardware like Big/IP or Cisco LocalDirector. - Perrin
RE: load balancing on apache
With this amount of connections, you may want to check LVS at http://www.linuxvirtualserver.com or Ultra Monkey et http://ultramonkey.sourceforge.net/(althought i never used the last one, I think it might be easier to use). This is open, efficient and reliableload balancing and high availability software. Using it, you just have to install several (common)apache server running your application, and tell the load-balancer to forward to one of the real servers. Nothing special to install exept an NFS or Coda service to share your Web sites. Fred -Message d'origine-De: Hemant Singh [mailto:[EMAIL PROTECTED]]Envoyé: vendredi 14 décembre 2001 09:51À: [EMAIL PROTECTED]Objet: load balancing on apache Hi All I am planning to host an application and its size is going to be big one , so expect the concurrent number of connection s to be around 2200.To combat the same , want to perform load sharing on 3-4 servers.So the ide is to put one machine on external IP and this machine , after receiving the requests would forward them to any of the other three machines having the application deployed and running on the same environment.Pls suggest how can i achieve this on apache. Thanks in advance Hemant
RE: load balancing on apache
Hi all, You can do load balancing using ipchains as well. Can't remember the program name offhand, but if I have time I'll look it up and let the list know. Only works if your servers are Linux of course. Kind regards Derek. --Derek Jones 1051, Bollinger Road,Tel: 717 359 8817 Littlestown,Mobile: 717 977 4556 PA, 17340, USAEmail: [EMAIL PROTECTED]AIM: scunacc
Re: load balancing on apache
Perrin Harkins [EMAIL PROTECTED] writes: I am planning to host an application and its size is going to be big one , so expect the concurrent number of connection s to be around 2200. To combat the same , want to perform load sharing on 3-4 servers. If you really expect 2200 concurrent connections, you should buy dedicated load-balancing hardware like Big/IP or Cisco LocalDirector. Aside from the fact I _really_ wouldn't expect that manny actual, live TCP connections at one time...that many users, maybe... I _really_ hate so-called dedicated boxes. They're closed, nasty, inflexible and often don't work in _your_ situation. Doing smart session-based redirection can be hard with these boxes. -- David Hodgkinson, Wizard for Hirehttp://www.davehodgkinson.com Editor-in-chief, The Highway Star http://www.deep-purple.com Deep Purple Family Tree news http://www.slashrock.com Interim Technical Director, Web Architecture Consultant for hire
Re: load balancing on apache
You should also check out Coyote Point's Equalizer ... this a
hardware/software solution that worked well for ValueClick up to about 70
million requests per day. It's basically a FreeBSD box with a custom
dynamic natd ... supports hot-swap redundancy with two of 'em installed
... and a _lot_ cheaper than LocalDirector and others (although we did
move to a high-end Foundry Server Iron system eventually) ... good support
from a small company too.
- nick
Nick Tonkin {|8^)
On Fri, 14 Dec 2001, Perrin Harkins wrote:
I am planning to host an application and its size is going to be big one ,
so expect the concurrent number of connection s to be around 2200.
To combat the same , want to perform load sharing on 3-4 servers.
If you really expect 2200 concurrent connections, you should buy dedicated
load-balancing hardware like Big/IP or Cisco LocalDirector.
- Perrin
RE: load balancing on apache
Well, Linux Virtual Server is using ipchains (on the load balancer), and you can use any kind of OS on your real servers (those running your application), since it's only TCP/IP routing and/or forwarding. Thanks Frederic, I had only ever hand-cranked this kind of setup manually with ipchains and not looked as LVS. 8-) Yes indeed, the OS you run it on is Linux as a load-balancing router, and yes, the balanced machines can be anything. I've run various Windoze machines (ulp!) behind this kind of setup. Kind regards Derek. --Derek Jones 1051, Bollinger Road,Tel: 717 359 8817 Littlestown,Mobile: 717 977 4556 PA, 17340, USAEmail: [EMAIL PROTECTED]AIM: scunacc
Re: load balancing on apache
Aside from the fact I _really_ wouldn't expect that manny actual, live TCP connections at one time... Nor would I, although we did see huge numbers of open connections during peak times at eToys. Mostly to the image serving machines though. I _really_ hate so-called dedicated boxes. They're closed, nasty, inflexible and often don't work in _your_ situation. Doing smart session-based redirection can be hard with these boxes. You can make it work with homegrown solutions, but I've found the dedicated load-balancing tools (at least Big/IP) to be effective and fairly easy to work with, even with large loads, failover requirements, and more exotic stuff like sticky sessions. This is one area where the problem seems to be well enough defined for most people to use an off-the-shelf solution. They're often more expensive than they should be, but if you don't have someone on hand who knows the ipchains or LVS stuff it can save you some time and trouble. - Perrin
Re: load balancing on apache
[EMAIL PROTECTED] wrote: You can make it work with homegrown solutions, but I've found the dedicated load-balancing tools (at least Big/IP) to be effective and fairly easy to work with, even with large loads, failover requirements, and more exotic stuff like sticky sessions. This is one area where the problem seems to be well enough defined for most people to use an off-the-shelf solution. They're often more expensive than they should be, but if you don't have someone on hand who knows the ipchains or LVS stuff it can save you some time and trouble. - Perrin If I'm not mistaken didn't the article about perl/mod_perl and etoys have some interesting things regarding load balancing? http://www.perl.com/pub/a/2001/10/17/etoys.html
Re: load balancing on apache
On Fri, 14 Dec 2001, Perrin Harkins wrote: I _really_ hate so-called dedicated boxes. They're closed, nasty, inflexible and often don't work in _your_ situation. Doing smart session-based redirection can be hard with these boxes. You can make it work with homegrown solutions, but I've found the dedicated load-balancing tools (at least Big/IP) to be effective and fairly easy to work with, even with large loads, failover requirements, and more exotic stuff like sticky sessions. This is one area where the problem seems to be well enough defined for most people to use an off-the-shelf solution. They're often more expensive than they should be, but if you don't have someone on hand who knows the ipchains or LVS stuff it can save you some time and trouble. I couldn't agree more. In terms of managability and scalability, the various software solutions simply add complexity to something that is already so. I've got some experience with Alteon AceDirectors and even though they seem little flakey at times, you do end up with true load balacing. (We have Cisco's solution deployed and they periodically have issues too.) DNS round-robin should be avoided at all costs. It's half-assed at best. In the case of a failure those clients that have that IP cached are SOL. On some of the systems that I've deployed we have a frontend proxy on the same box as the mod_perl with the mod_perl server listening on 127.0.0.1. This is behind an Alteon (or 2). You can put the proxy on a separate box as well but (I've seen some odd problems with TCP connections not working in this situation which I never fully understood but may have had to do with the Alteon being flakey.) Anyway, my advice is to go with a hardware load balancer/intelligent IP switch. In the long term, it will pay for itself in the time recovered from *not* being spent on troubleshooting complex problems. --Jeff -- They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety. - Benjamin Franklin, Historical Review of Pennsylvania, 1759.
Re: load balancing on apache
At least one person MUST mention Backhand! www.backhand.org I'm working on a project right now that is expected to grow to 100+ servers in the next 12 months. In past projects I've worked on, handling of the log files becomes non-trivial at numbers far below that, so I built the new system to log via Spread (www.spread.org) and it is a wonderful thing to behold. When you start building really big systems, the insignificant things become big things, and the big things become huge! :-) On a side note: we originally used mod_log_spread to log via Spread, but found it to be a fairly nasty solution (lots of errors in the log files, otherwise worked OK) so we instead used good old mod_log_config and piped the output to a Perl program that spreads the logs. -- -- Tom Mornini -- InfoMania Printing Prepress
Re: load balancing on apache
Jeff Beard wrote: On Fri, 14 Dec 2001, Perrin Harkins wrote: I _really_ hate so-called dedicated boxes. They're closed, nasty, inflexible and often don't work in _your_ situation. Doing smart session-based redirection can be hard with these boxes. You can make it work with homegrown solutions, but I've found the dedicated load-balancing tools (at least Big/IP) to be effective and fairly easy to work with, even with large loads, failover requirements, and more exotic stuff like sticky sessions. This is one area where the problem seems to be well enough defined for most people to use an off-the-shelf solution. They're often more expensive than they should be, but if you don't have someone on hand who knows the ipchains or LVS stuff it can save you some time and trouble. I couldn't agree more. In terms of managability and scalability, the various software solutions simply add complexity to something that is already so. I've got some experience with Alteon AceDirectors and even though they seem little flakey at times, you do end up with true load balacing. (We have Cisco's solution deployed and they periodically have issues too.) DNS round-robin should be avoided at all costs. It's half-assed at best. In the case of a failure those clients that have that IP cached are SOL. On some of the systems that I've deployed we have a frontend proxy on the same box as the mod_perl with the mod_perl server listening on 127.0.0.1. This is behind an Alteon (or 2). You can put the proxy on a separate box as well but (I've seen some odd problems with TCP connections not working in this situation which I never fully understood but may have had to do with the Alteon being flakey.) Anyway, my advice is to go with a hardware load balancer/intelligent IP switch. In the long term, it will pay for itself in the time recovered from *not* being spent on troubleshooting complex problems. yes. It's a money vs. time/knowledge thing. Plus the state of the free software available. Anyone care to compare the features and power of some of the opensource projects vs. the Big/IP's? Which are the more promising opensource projects in this area? It would be nice to use an open source solution, or at least be able to offer it as an option, and I'd like to track the progress of some of the more promising projects. Ed Ed
Re: load balancing on apache
I think you also have to specify weather your web applications are state-less or not. If stateless, then you can just use DNS Round Robin technique or lbnamed (Load Balancing Name Server) to achieve this load balancing or high availability. If your apps are statefull as in ASP, Cold Fusion, JSP, etc, then you'll need to retain the sessions and that becomes more complicated but possible. On Fri, 14 Dec 2001, Hemant Singh wrote: Hi All I am planning to host an application and its size is going to be big one , so expect the concurrent number of connection s to be around 2200.To combat the same , want to perform load sharing on 3-4 servers.So the ide is to put one machine on external IP and this machine , after receiving the requests would forward them to any of the other three machines having the application deployed and running on the same environment.Pls suggest how can i achieve this on apache. Thanks in advance Hemant -- - Medi Montaseri [EMAIL PROTECTED] Unix Distributed Systems EngineerHTTP://www.CyberShell.com CyberShell Engineering -
Re: load balancing on apache
My recommendation is that you do none of the things that you are looking at for optimal performance. Instead, opt for a seperate hardware solution. We went through this about a year ago when we were architecting a solution for my employers site. Admittedly, takes more traffic than you do, but we found that the dedicated hardware device offers many advantages (including layer 7 routing capablity) which we have found to be extremely useful and well worth the extra cabbage. Cisco (and several other folks as well) make some fine load balancing hardware devices. Alteon makes one, I know . We evaluated it, but we got a better price and better support from Cisco so we went with the CSS even though I was as impressed with their device. I'm sure that there are lower end alternative, but it depends on what kind of load balancing you want to do. Do you want to do round robin? If not, then what criteria do you want to use? - Original Message - From: Steven Lembark [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Friday, December 14, 2001 3:15 AM Subject: Re: load balancing on apache -- Hemant Singh [EMAIL PROTECTED] Hi All I am planning to host an application and its size is going to be big one , so expect the concurrent number of connection s to be around 2200.To combat the same , want to perform load sharing on 3-4 servers.So the ide is to put one machine on external IP and this machine , after receiving the requests would forward them to any of the other three machines having the application deployed and running on the same environment.Pls suggest how can i achieve this on apache. Randal Schwartz had a good article on this about a year ago. You can use the re-write phase to balance the load w/in Apache if you want to. Alternatives include round- robin DNS and separate load balancing software. -- Steven Lembark 2930 W. Palmer Workhorse Computing Chicago, IL 60647 +1 800 762 1582
Re: load balancing on apache by IP CHAINING
IP chaining can be done in Java Webserver, How to do it in Apache Webserver. Please let the Ring know this, Thanks in advance, Regards, Anand - Original Message - From: Derek Jones To: Hemant Singh ; [EMAIL PROTECTED] Cc: Derek G Jones Sent: Friday, December 14, 2001 7:29 PM Subject: RE: load balancing on apache Hi all, You can do load balancing using ipchains as well. Can't remember the program name offhand, but if I have time I'll look it up and let the list know. Only works if your servers are Linux of course. Kind regards Derek. --Derek Jones 1051, Bollinger Road,Tel: 717 359 8817 Littlestown,Mobile: 717 977 4556 PA, 17340, USAEmail: [EMAIL PROTECTED]AIM: scunacc
