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46

Simply put.. HaProxy is the best opensource loadbalancer on the market. Varnish is the best opensource static file cacher on the market. Nginx is the best opensource webserver on the market. (of course this is my and many other peoples opinion) But generally.. not all queries go through the entire stack.. Everything goes through haproxy and nginx/...


27

The website runs on a server process. When you shut down the server process, the server does not magically turn off. Also not when you misconfigure your firewall (and block port 80) neither does the server go off nor does the ICMP rule in the firewall get deleted.


20

I've not actually followed your link (no desire to meet a zero-day exploit), but what often happens when a server has been hacked is that code is put into any PHP files to check the referrer header and redirect either if the visit is from a search engine or if it's from anywhere not the current site. This is done to try to prevent the owner of the site from ...


19

Your DNS should not change very often in the first place. Many DNS server do not honor your TTL "request" and impose their own policy. If you're going to make a chage, set the TTL lower weeks before the change. Normally having a long TTL helps reduce load on your authoritative server(s) and adds a bit of time to clients accessing your site. I commonly use ...


18

It's true that the 3 tools share common features. Most setups are fine with any combination of 2 among the 3. It depends what their main purpose is. It's common to accept to sacrifice some caching if you know your application server is fast on statics (eg: nginx). It's common to sacrifice some load balancing features if you're going to install tens or ...


17

The additional security surface java puts into your environment is complex, and it's important not to ignore it or try to simplify it away. Firstly, there is the horrible record the JRE has for having security bugs. It's hard to point out a specific one, and this is the scary part - the bugs are overwhelmingly unspecified vulnerabilities with unspecified ...


16

As Ron Garrity says, you can use Curl like this: curl -Iv http://www.aptivate.org 2>&1 | grep -i 'connection #0' And it outputs these two lines if keep-alive is working: * Connection #0 to host www.aptivate.org left intact * Closing connection #0 And if keep-alive is not working, then it just outputs this line: * Closing connection #0


15

Well, 1.1.1.1 is an IP address. As far as who it is - it's public address space that bad internet citizens tend to use as a placeholder: inetnum: 1.1.1.0 - 1.1.1.255 netname: Debogon-prefix descr: APNIC Debogon Project descr: APNIC Pty Ltd country: AU admin-c: AR302-AP tech-c: AR302-AP mnt-by: ...


13

A domain that serves no cookies. The idea here is that you use a cookie-free domain to serve images, CSS files, scripts and whatnot, so that your users don't waste time and bandwidth transmitting cookies for them. SO uses sstatic.net for the purpose, for example. The main reason the concept is of any note is that most people can't use a subdomain of their ...


13

When viewing the source of your page, there's some code at the bottom that doesn't look like you put there: <div style='position:absolute;left:-2125px;width:1024px'><a href='http://www.asrtu.org/trust_crcks/passware-myob-key-crack.html'>Passware MYOB Key crack</a></div><div style='position:absolute;left:-2125px;width:1024px'>&...


12

Pros of using a Mac Mini as a server None Cons of using a Mac Mini as a server No redundancy No rackability No hardware battery-backed RAID Not serviceable Non-ECC memory Crap cooling Not built for load Not scalable Poor support under non-Mac operating systems What, then? There are many, many places where you can get dedicated servers for $200 or less ...


12

I have done exactly what you speak of before. I found the industry has a very strong barrier to entry, but here is what I did. Rented a dedicated server with a control panel, in my case Plesk (linux or windows) Bought a domain name to be the "home" of my hosting business The server you buy will likely come with 4-7 IP addresses, you can use these to ...


12

There are many methods for scaling web applications and the supporting infrastructure. Cal Henderson wrote a good book on the subject called "Building Scalable Web Sites". It was based on his experiences with Flickr. Unless you grow slowly you will run into the same kinds of growth issues many others have seen. Scaling is, like many other subjects, a ...


12

I suggest you reevaluate your reasons for wanting to go the commercial route rather than using an opensource solution such as Squid. Squid is used by many large ISPs worldwide and is quite likely the most mature web cache and proxy available. Apart from the cost benefit of not requiring any license fees, Squid has an active community and hundreds of code ...


12

Depending on your version of chmod, you may be able to do this: chmod -R . ug+rwX,o+rX,o-w Note the capital X. This sets the executable bit on directories and files that already have any of the execute bit already set. Note that you can only use capital X with '+', not '=' or '-'.


12

First, my condolences on your mentor's hospitalization and your baptism by fire into system administration. Second, my condolences on your data loss. I sincerely hope you have backups. To summarize your situation: You have a three-drive RAID array (presumably a RAID-5). This is one "Logical Drive" (the 3 disks are handled by the RAID controller, and ...


11

The first thing I would do is to take it off the net at least till I understand what exactly is the damage. Assessing what has been compromised in a timely manner is most crucial.


11

question 2 It looks like the name servers and actual host for YOGOTAGIFT.COM are registered through ENOM, Inc. The site is hosted at EHOST-SERVICES212.COM. Try sending both spam reports and DMCA takedown notices to eNom and the server host. eNom abuse page is http://www.enom.com/help/abusepolicy.aspx question 4 : Honeytokens Seed your mailing list and ...


10

All other answers are pre-2010, hence adding an updated comparison. Nginx A full web server, other features can also be used. Eg: HTTP Compression SSL Support Very light weight as Nginx was designed to be light from the start. Near Varnish caching performance Close to HAProxy load balancing performance Varnish best for complex caching scenarios and ...


10

Traceroute uses ICMP protocol to reach an address, and a HTTP server use HTTP protocol, different ports, and different approaches. I can reach an address via ICMP echo request but, if the port I'm trying to communicate is closed or freezed somehow, I'll get a timeout error. And if you're sure the server is up and the port is up (listening), is better to ...


9

here is a trick i use all the time... :) it assumes you control the current server. put the site/db/whatever on the new server and on your old/current server, enable the proxy, proxy_http and the rewrite modules, then add the following lines on the apache config file for your old/current site: RewriteEngine on ProxyPass / http://<your-fqdn-...


9

The main argument I have seen against them is that files that are common to many servers will have to be grabbed over and over again by the client. Better is to include a version string in the name of the file itself. So for example, if you round robin load balance your web servers each server will generate its own ETag causing the client to grab it ...


9

That is a very intelligent question and a clear cut source of confusion when ops and devs talk. It means different things depending on context, and especially so in a web hosting context. root can as far as I know officially mean at least: the system full access privileges user. the file system base directory, a.k.a. / the web server shared file system ...


8

Squid doesn't care what type of system is initiating web traffic, so you can just continue to use Squid, although there is a Windows port if you want to run Squid on Windows for some reason (http://squid.acmeconsulting.it/SquidNT26.html). If you are looking to become a Microsoft shop, then Internet Security and Acceleration Server (more commonly known as ...


8

Maybe Gosa will fit... I haven't try it yet but it's on my TODO. From the homepage it says: GOsa² provides a powerful GPL'ed framework for managing accounts and systems in LDAP databases. Using GOsa² allows system administrators to easily manage users and groups, fat and thin clients, applications, phones and faxes, mail distribution lists ...


8

Personally, I think nginx provides the right split between the things it does itself (receiving and processing HTTP requests) and what it delegates to other processes (dynamic page generation). Whilst it is less effort to setup Apache to serve PHP requests, running everything within Apache is a bit of a security and configuration problem (all files that are ...


7

I also looked at this on the Nginx wiki and other blogs and the best way performance wise is to do the following: To redirect from www.example.com to example.com using nginx (version 1.0.12 at time of writing). server { server_name www.example.com; rewrite ^ $scheme://example.com$request_uri permanent; # permanent sends a 301 redirect whereas ...


7

I've had good results from wapiti - it scans your web forms and attempts injections and XSS attacks against them. If you have the time, I'd suggest getting the backtrack distribution - it's a modified ubuntu liveCD that's been loaded up with nikto, wapiti, openVAS (a fork of nessus) and hundreds of other great security audit tools; I've used it in a few ...


7

Have you looked at roundcube?


7

The cause of this problem is that in EU countries (and certain other TLDs outside the USA), nameserver records are typically cached for more than 1 day. SBS2008 has a cap on the maximum time that it will allow nameserver records to be cached, which defaults to 1 day. This default works fine in the USA but When the .uk and .eu records become stale, they are ...



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