Search Results

Search found 14213 results on 569 pages for 'distributed programming'.

Page 464/569 | < Previous Page | 460 461 462 463 464 465 466 467 468 469 470 471  | Next Page >

• Squid on windows loadbalancing only to one server

  - by Martin L.

  After thousands of googles and trying days i cant get the load balancer/failover in squid on windows to work. Iam using squid 2.7. My webservers are 2 single NIC lighttpd and one dual nic lighttpd. server1 in this example is running squid on port 80 and lighttpd on port 8080 (just to test) Requirements: All 3 webservers running lighttpd should be balanced two option for load balancing: Best would be if server1 is busy server2 takes over, if server2 is busy server3 takes over, etc.. Round robin style evenly distributed load. Eg server1 takes first call, server2 second etc.. All requests should be treated the same way (no url rewriting or so on) Sent host headers have to be redirected to every server as http host header, speaking of "server1", "server1.company.internal" and "10.211.1.1". My approach: acl all src all acl manager proto cache_object http_port 80 accel defaultsite=server1.company.internal vhost #reverse proxy entries cache_peer 10.211.2.1 parent 8080 0 no-query originserver round-robin login=PASS name=server1_nic1 cache_peer 10.211.1.2 parent 80 0 no-query originserver round-robin login=PASS name=server2_nic1 cache_peer 10.211.2.3 parent 8080 0 no-query originserver round-robin login=PASS name=server3_nic1 cache_peer 10.211.2.4 parent 8080 0 no-query originserver round-robin login=PASS name=server3_nic2 #decl of names of squid host acl registered_name_hostdomain dstdomain server1.company.internal acl registered_name_host dstdomain server1 #ip of squid host acl registered_name_ip dstdomain 10.211.2.1 # access: redirects the correct squid hostname http_access allow registered_name_hostdomain http_access allow registered_name_host http_access allow registered_name_ip http_access deny all cache_peer_access server1_nic1 allow registered_name_hostdomain cache_peer_access server1_nic1 allow registered_name_host cache_peer_access server1_nic1 allow registered_name_ip cache_peer_access server2_nic1 allow registered_name_hostdomain cache_peer_access server2_nic1 allow registered_name_host cache_peer_access server2_nic1 allow registered_name_ip cache_peer_access server3_nic1 allow registered_name_hostdomain cache_peer_access server3_nic1 allow registered_name_host cache_peer_access server3_nic1 allow registered_name_ip cache_peer_access server3_nic2 allow registered_name_hostdomain cache_peer_access server3_nic2 allow registered_name_host cache_peer_access server3_nic2 allow registered_name_ip cache_peer_access server1_nic1 deny all cache_peer_access server2_nic1 deny all cache_peer_access server3_nic1 deny all cache_peer_access server3_nic2 deny all never_direct allow all Problems: Load balancer does not load balance other than to first server. Only if the first server is killed in any way the second will take over. I have seen the others working at some point, but definitely not as the intended load balancing described above. If the cache_peer_access is not defined sometimes the wrong hostname is sent to the backend webserver and this always depends on the defaultsite= parameter. Probably because the host header on the request to squid is not set and its replaced by defaultsite. Leaving out defaultsite didnt solve the problem. The only workaround i found for this is the current approach with cache_peer_access. Questions: Does the cache_peer_access influence the round-robin? Is there a better workaround to pass the host header to the backed webservers? Which parameters do increase the speed of load balancing or does anyone have a better approach? -Martin

  Read the article

• Bash variable kills script execusion

  - by Kyle Terry

  Sorry if this is better suited at serverfault, but I think it learns more towards the programming side of things. I have some code that's going into /etc/rc.local to detect what type of touch screen monitor is plugged in and changes out the xorg.conf before launching X. Here is a small snippet: CURRENT_MONITOR=`ls /dev/usb | grep 'egalax_touch\|quanta_touch'` case $CURRENT_MONITOR in '') CURRENT_MONITOR='none' ;; esac If one of those two touch screens is plugged in, it works just fine. If any other monitor is plugged in, it stops at the "CURRENT_MONITOR=ls /dev/usb | grep 'egalax_touch\|quanta_touch'." For testing I touched two files. One before creating CURRENT_MONITOR and one after CURRENT_MONITOR and only file touched before is created. I'm not a bash programmer so this might be something very obvious.

  Read the article

• VB6 Parser/Lexer/Scripter

  - by rlb.usa

  I've got a game in VB6 and it works great and all, but I have been toying with the idea of creating a scripting engine. Ii'm thinking I'd like VB6 to read in flat text script files for me and then lex/parse/execute them. I have good programming experience, and I've built a simple C compiler, as well as a LOGO emulator before. My question is: Are there any tools that I can use, like Lexx/Yakk/Bison to help me? How should I approach this problem in regards to lexing, parsing, and feeding the commands back to VB6 so I can handle them? Is this idea a BAD IDEA in the sense that there are too many obstacles in the way (For example, building minesweeper in assembly, though not impossible, is very difficult, and a bad idea.)?

  Read the article

• How to write applications that modifies the Windows UI?

  - by StevenGilligan

  Hi, I have this programming question that's been bothering me for some time now. I'm wondering how is it possible to write applications that change the Windows UI? More precisely how could you write an application that modifies the Windows Taskbar or the Windows Desktop? I'm really interested in this topic but cannot find a lot of information. I've read about extending the Windows Shell but I can't seem to find anything related to modifying the Taskbar and the Desktop. I'm looking for something along the lines of Rainmeter. How did those guys create an application that lives inside the Windows Desktop? I'd like to point out that my prefered language for this would be C# but if you want to give me hints in other languages I'm fine with it and I am running on Windows 7. Thank you

  Read the article

• Learning Objective-C 2.0 and ASP.NET 4.0 simultaneously?

  - by Sahat

  (HOBBY) I own a Macbook Pro and iPod Touch so developing iPhone/iPod/iPad apps seems like a logical thing to do in order to get some experience in the programming field. Besides I want to write a new application similar to the Capsuleer (Character skills monitor app for EVE Online MMO) but with more features. It's something I'd love to have on my own iPod Touch and I am sure other people will welcome a new EVE Online app for their iPhone or iPod Touch. (CAREER) I want to learn ASP.NET (and possibly Silverlight later on) for my potential future job. I plan to work in the .NET field, so it's a good idea for me to start learning C# and ASP.NET ASAP. Is it a good idea to learn completely unrelated technologies at the same time? Or would it be better to learn one thing at a time? Objective-C first, and ASP.NET second. Or vice versa. Thanks, Sahat

  Read the article

• What are some of the useful concepts to know about when building Silverlight apps?

  - by cody

  The Silverlight(& WPF) space seems to have a whole new nomenclature around it so at times I'm having a hard time figuring our what is important and useful to research a bit more. For example I 'know' about the MVVM pattern but I'm looking for things that are a bit smaller in scope, that is topics, ideas, programming constructs that might be used in implementing MVVM and would need to know before hand. So basically I'm looking for some of the key topics and concepts that people have found useful or are important when creating a Silverlight apps. And maybe why it is useful or important and when\where it might be applied or used. Thanks.

  Read the article

• help in security assignment

  - by scatman

  i have to write a program that sniffs network packets (part1-the simple part). and i have to update the program (part2) so that it will be able to terminate connections. the specific requirements are: construct raw packets by specifying data link layer and network layer information including appropriate source and destination MAC and IP addresses. These packets are intended to terminate the connection. To do so, you should used SOCK_RAW as the socket type to be able to set the header information by yourself. can anybody give me some ideas on the second part? should i hijack the session,apply a dos attack on one of the users?? all i need is some tips of how to terminate the connection. i am using c programming language. and this is a course assignment for the security course.

  Read the article

• Does Mobile phone have Server : Port Scheme ?

  - by MilkBottle

  Hi I hope I can get all the help i can get here. I am new to mobile phone programming. I find networking very interesting and I have this question: Does Mobile phone like WinMo or other phone have Server:Port scheme and what are the ports ? To show what I mean, I use PC to demonstarte, there are many ports ( restricted and established ). The below is the Server : Port scheme Server : port example WebServer 80 So, to use a TCPListener on PC , I can use any port as long as there are not restricted and establsihed) to listen incoming TcpClient . 2) How do I use a TCPListener and Which portNo I need to use to listen incoming TcpClient from the other end in Net Compact Framework? Thanks

  Read the article

• How do I use compiler intrinsic __fmul_?

  - by Eric Thoma

  I am writing a massively parallel GPU application. I have been optimizing it by hand. I received a 20% performance increase with _fdividef(x, y), and according to The Cuda C Programming Guide (section C.2.1), using similar functions for multiplication and adding is also beneficial. The function is stated as this: "_fmulrn,rz,ru,rd". __fdividef(x,y) was not stated with the arguments in brackets. I was wondering, what are those brackets? If I run the simple code: int t = __fmul_(5,4); I a compiler error about how _fmul is undefined. I have the CUDA runtime included, so I don't think it is a setup thing; rather it is something to do with those square brackets. How do I correctly use this function? Thank you.

  Read the article

• Project Euler #163 understanding

  - by Paul

  I spent quite a long time searching for a solution to this problem. I drew tons of cross-hatched triangles, counted the triangles in simple cases, and searched for some sort of pattern. Unfortunately, I hit the wall. I'm pretty sure my programming/math skills did not meet the prereq for this problem. So I found a solution online in order to gain access to the forums. I didn't understand most of the methods at all, and some just seemed too complicated. Can anyone give me an understanding of this problem? One of the methods, found here: http://www.math.uni-bielefeld.de/~sillke/SEQUENCES/grid-triangles (Problem C) allowed for a single function to be used. How did they come up with that solution? At this point, I'd really just like to understand some of the concepts behind this interesting problem. I know looking up the solution was not part of the Euler spirit, but I'm fairly sure I would not have solved this problem anyhow.

  Read the article

• Is it secure to use malloc?

  - by Felix Guerrero

  Somebody told me that allocating with malloc is not secure anymore, I'm not a C/C++ guru but I've made some stuff with malloc and C/C++. Does anyone know about what risks I'm into? Quoting him: [..] But indeed the weak point of C/C++ it is the security, and the Achilles' heel is indeed malloc and the abuse of pointers. C/C++ it is a well known insecure language. [..] There would be few apps in what I would not recommend to continue programming with C++."

  Read the article

• Suggest a open source project which heavily uses java concurrency utilities?

  - by user49767

  I have done good amount of Java programming, but yet to master Threading & Concurrency. I would like to become an expert programmer in threading & concurrency. I have also took a short at Tomcat code, I was able to understand, but looking even more complex project. Could you suggest any open source project which heavily uses java threading & concurrency utilities? Note : I have also reading java.util.concurrent package source code, but eager to learn from Application perspective, than creating my own threading utilities.

  Read the article

• Using a proxy for NSURLConnection

  - by SideSwipe

  Is there any way to get the content of a webfile (namely a .html Document) using a proxy, which is not defined in the system settings? I know that NSURLConnection is the right way to download a web file into a variable and not into a file (for which we should use NSURLDownload), but I don't find a way to use a proxy for it. Are there some unofficial APIs, Libraries or Classes or such I could use for what I want to do? I'm not that pro in Mac Programming, so I'm searching for something more or less simple. SideSwipe

  Read the article

• How to integrate access control with my ORM in a .net windows form application?

  - by Ying

  I am developing a general database query tools, a .Net 3.5 Windows Form application. In order to make the presentation layer is independent of the database layer. I use an ORM framework, XPO from DevExpress. But, I have no access control function built in. I surfed Internet and I found in WCF Data Services, there is an interesting concept, Interceptor, which is following AOP(Aspect Oriented Programming). I am wondering who has such an experience to build access control in ORM. My basic requirement is : It should be a general method and controlled by users in runtime. So any hard coding is not acceptable. It could be based on attribute, database table, or even an external assembly. I am willing to buy a ready solution. According to the idea of AOP, an access control function can be integrated with existing functions easily and nearly not knowingly to the previous developer;) Any suggestions are welcome.

  Read the article

• data parsed to database Nokogiri rails

  - by Charlie Allombert

  So I'm just getting started with Nokogiri and Rails I have the following which returns the name of someone. TEST.rb: require 'nokogiri' require 'open-uri' url = "http://www.imdb.com/title/tt1439629/" doc = Nokogiri::HTML(open(url)) puts doc.css("div#wrapper [...too long...]")[0].text Now I created a table in my DB on rails and want to send the returned name to the actor table in the name column! How would I do that ? I can't seem to find atutorial on this... My goal would eventually be to have a rails form where I'd input an IMDB link which would return title and so on... (Also I'm new to ruby rails and programming so please provide easy info!)

  Read the article

• Creating a unique id for a Core Data program on the iPhone

  - by Big Twisty

  I am fairly new at programming in Objective-C, having been a windows programmer since I was a kid. I am falling in LOVE with it. I am, however, having a bit of trouble figuring out this Core Data stuff. How do I create a new entry with a unique ID? In SQL I would just declare one field as an autoincrement field. I'm not seeing anything like that here, but I could just be missing something. I just want an auto incrementing NSInteger field, so when I manually add items to the database, I will have some form of reference to them.

  Read the article

• Connecting a PHP front-end to a back-end java service

  - by christopher-mccann

  I am currently using various back-end services and I want to use PHP to simply query these services and perform the final page construction. These services could be coded in any number of programming langauges such as Erlang, Java, Python etc. However I am unsure of the best way to actually interface the back-end services with the web app. Requests to these services would be both synchronous and asynchronous. Would I use something like SOAP or JSON-RPC?? Any help greatly appreciated.

  Read the article

• How Does Facebook Know What Image To Parse Out of An Article?

  - by Travis

  First off I want to say that I wasn't really sure where to post this but it is very much programming related. If it is in the wrong spot I apologize and please let me know where I should post it instead. When sharing an article on a friends wall, facebook will grab a thumbnail of the article. How do they always get the right thumbnail from articles? It doesn't grab the logo img element of of http://www.nytimes.com/2010/06/07/world/asia/07convoys.html?hp for example but rather grabs the correct image element that corresponds with the article. I'm looking to do something similar and was wondering of a good way to parse the html to find the image given this example. Thanks.

  Read the article

• bitshift large strings for encoding QR Codes

  - by icekreaman

  As an example, suppose a QR Code data stream contains 55 data words (each one byte in length) and 15 error correction words (again one byte). The data stream begins with a 12 bit header and ends with four 0 bits. So, 12 + 4 bits of header/footer and 15 bytes of error correction, leaves me 53 bytes to hold 53 alphanumeric characters. The 53 bytes of data and 15 bytes of ec are supplied in a string of length 68 (str68). The problem seems simple enough - concatenate 2 bytes of (right-shifted) header data with str68 and then left shift the entire 70 bytes by 4 bits. This is the first time in many years of programming that I have ever needed to do something like this, I am a c and bit shifting noob, so please be gentle... I have done a little investigation and so far have not been able to figure out how to bitshift 70 bytes of data; any help would be greatly appreciated. Larger QR codes can hold 2000 bytes of data...

  Read the article

• Question about OOP and objects.

  - by loddn

  I have a school assignment, a Dog Show. My assignment is to create a website where vistors can display results and Judges and Secretary can admin, crud. I have a small problem one part of the assignment. The result should be based on two protokols from different judges and after that checked by the secretary before the result is displayed for the user. I have to say i'm fairly new to programming and so i need some smart suggestions on how to design and implement this. The assignment should cover both a db and c# (.net mvc). Q1: How do i create a object (result)that depends on two other objects(protocol)? Is that even needed? Q2: How to solve this in a relational db?

  Read the article

• Will sharpening my sword eventually lead to it cutting my head off?

  - by Achilles

  Sharpening the sword: All I've read in the developer community suggests that I should keep learning and studying to become the best developer I can. This will make me better at my job and more valuable as an employee. Cutting my head off: However there seems to be an influx of cheap programming labor constantly coming int to the market(college, foreign countries, etc.) I was part of that influx when I graduated. So my question is, What is the likely outcome? Will there always be a job where a skilled-programmer(Grey-Beard) will have a place to work and contribute, or will he eventually price himself out of the market by having such great knowledge and skill?

  Read the article

• Easy way to replicate web page across machines?

  - by Mike_G

  I am trying to replicate a browser page to another browser on another machine. I basically want to reproduce a page exactly how it appears to a customer for viewing by the website owner. I have done this before using some impersonation trickery, but found that it would throw the session state out of wack when the site owner would switch customers. So I would like to stay away from cookie and authentication manipulation. Anybody done anything like that? Is there a way to easily transfer the DOM to a webservice? The tech/programming at my disposal are C#, javascript, WCF.

  Read the article

• which layout engine for finding coordinates of html elements on the web page?

  - by Mexx

  I am doing some web data classification task and was thinking if I could get the co-ordinates of html elements as they would appear on a web-browser without taking into consideration any css or javascript being referred in the web page. My language of programming is c++ and the need results for a couple million of pages, so it has to be fast. I know there is a Microsoft COM component which renders the page in a web browser control and then can be queried for position of different html tags. But this is not suitable in my case as it first renders the whole page which takes up a lot of time. So as I found out, there are open-source layout engines WebKit, Gecko that can probably be used for this. But that's a huge piece of code and I need someone to direct me to the right classes or right modules to look into or any previous/similar work someone has done previously. Also, please let me know what you guys think is a good choice if I want to customize the existing code for use with multiple threads to make it faster. Thanks

  Read the article

• Learning OpenGL ES 1.x

  - by Kristopher Johnson

  What is the quickest way to come up to speed on OpenGL ES 1.x? Let's assume I know nothing about OpenGL (which is not entirely true, but it's been a while since I last used OpenGL). I am most interested in learning this for iPhone-related development, but I'm interested in learning how it works on other platforms as well. I've found the book OpenGL ES 2.0 Programming Guide, but I am concerned that it might not be the best approach because it focuses on 2.0 rather than 1.x. My understanding is that 2.0 is not backwards-compatible with 1.x, so I may miss out on some important concepts. Note: For answers about learning general OpenGL, see http://stackoverflow.com/questions/62540/learning-opengl Some resources I've found: http://khronos.org/opengles/1_X/ http://www.imgtec.com/powervr/insider/sdk/KhronosOpenGLES1xMBX.asp OpenGL Distilled by Paul Martz (a good refresher on OpenGL basics)

  Read the article

• n00b: receive input over TCP/IP and use it to update HTML

  - by mawg

  This has got to be a FAQ, so can someone please just direct me to a "network programming for dummies" URL? The server wants to push information to a client or broadcast to all, when an event happens - as opposed to the clients constantly polling the server "just in case". The client then updates a browser page display. How do I do that? (toldya it was a n00b question) Should I have a thread which receives info on a socket and then writes it to a database which the browser display (PHP) can process with an HTML refresh tag, or what? Sorry to sound so dumb.

  Read the article

< Previous Page | 460 461 462 463 464 465 466 467 468 469 470 471  | Next Page >