Having a reverse-proxy web cache as one of the major infrastructure elements brings many benefits for large web applications: it reduces your application servers load, reduces average response times on your site, etc. But there is one problem every developer experiences when works with such a cache – cached content invalidation.
It is a complex problem that usually consists of two smaller ones: individual cache elements invalidation (you need to keep an eye on your data changes and invalidate cached pages when related data changes) and full cache purges (sometimes your site layout or page templates change and you need to purge all the cached pages to make sure users will get new visual elements of layout changes). In this post I’d like to look at a few techniques we use at Scribd to solve cache invalidation problems.
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This is going to be a really short post, but for someone it could save an hour of life.
So, you’ve nothing to do and you’ve decided to play around with IPv6 or maybe you’re happened to be an administrator of a web service that needs to support IPv6 connectivity and you need to make your nginx server work nicely with this protocol.
First thing you need to do is to enable IPv6 in nginx by recompiling it with --with-ipv6 configure option and reinstalling it. If you use some pre-built package, check if your nginx already has this key enabled by running nginx -V.
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Month ago I was on a vacation and as usual even though our hotel provided us with an internet connection on a pretty decent speeds, I wasn’t able to work there because they’ve banned all tcp ports but some major ones (like 80, 21, etc) and I needed to be able to use ssh, mysql, IMs and other non-web software.
After a short research I’ve found a pretty simple to set up and easy to use approach to such a connection problems I’d like to describe here.
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Many people know me as a nginx web server evangelist. But as (IMHO) any professional I think that it is really rewarding to know as much as possible about all the tools available on the market so every time you need to make a decision on some technical issue, you’d consider all pros and cons based on my own knowledge.
This is why when I received an email from Packt company asking if I’d like to read and review their book on Lighttpd I decided to give it a shot (I usually do not review any books because I do not always have enough time to read a book thoroughly to be able to write a review). So, here are my impressions from this book.
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