I use NGINX for various things, including one niche case, where I rewrite and replace strings before presenting them to the user. I do this using the HTTP substitutions filter module. The readily-compiled module to accomplish this is included with the paid NGINX Plus, but is also available to DIY compile if you have the ability.
If you're just looking for precompiled .so files you can use with NGINX on CentOS 7 available from the nginx.org repository, see the end of this post.
A while ago I took the time to work out how to compile this for updates; the CentOS box I run NGINX on uses yum packages for updates, but then the subs filter module stops working. So, after half an hour or so of tinkering, quiet swearing, obtaining of additional packages, tweaking commandlines etc... I have a working oneliner to make an NGINX build which will also compile a suitable
To compile this dynamic module you generally need to build with the same switches used for the packaged build. So, first step was to find out how it was compiled:
See how to check your compile flags, and how to build from source
Fail2ban's official compile for CentOS6 has never advanced beyond 0.9.6-1.el6.1. While 0.9.6 works, it's old and has a few major inconveniences:
- No IPv6 support 🙁
- A tendency for the daemon to die when parsing many logs or a high volume of activity
- Quite slow to parse logs when restarting after a config change
So, what can we do? Well, compile from source and upgrade with the supplied python script! It's easier than I anticipated, but there's still a few things you need to watch out for.
I noticed recently that a few web sites are miscategorising my ISP's static IP as being in the wrong country. I knew it was a recent reallocation of a new block and suspected the web sites were using a stale version of a GeoIP database - probably MaxMind's GeoLite v1 offering.
If you see stuff like this while surfing the web, your IP is probably in the same boat:
It's such a stupid problem, but it's all due to lazy server admins or designers