--- title: "Apache 2.4 on RHEL 6 from Software Collections" date: "2014-10-02" path: "/175-apache-2-4-on-rhel-6-from-software-collections.html" section: "/ramblings" description: "Installing the httpd24 Software Collection alongside Apache 2.2 on RHEL 6, pointing a Virtualmin server at it and fixing the 2.2 config so it starts." --- RHEL 6 ships Apache 2.2.15 and that is what it will stay on for the life of the release. If you want 2.4 (event MPM, `Require` access control, better proxy and FastCGI support) you don't replace the system package, you install 2.4 next to it from a Software Collection. My [short note from a few days ago](/174-rhel-6-x-and-apache-2-4.html) got it running; this is the full version, including the parts that bit me when I pointed an existing Virtualmin server at it. ## Where to get httpd24 There are two sources: - Red Hat Software Collections. On a subscribed RHEL 6 box enable the RHSCL channel and install from there. This is the supported route. - Jan Kaluza's repository on fedorapeople.org. He maintains the httpd packages at Red Hat and published the collection there first. It works on CentOS 6 and on RHEL boxes without the RHSCL entitlement. ```bash # RHEL with a Software Collections subscription subscription-manager repos --enable rhel-server-rhscl-6-rpms yum install httpd24 httpd24-mod_ssl # or the community repository curl -s https://repos.fedorapeople.org/repos/jkaluza/httpd24/epel-httpd24.repo > /etc/yum.repos.d/epel-httpd24.repo yum install httpd24-httpd httpd24-mod_ssl ``` ## Where everything lives A collection installs under `/opt/rh//root`, so nothing collides with the base system. Check what you got: ```bash rpm -ql httpd24-httpd | grep sbin ``` ```text /opt/rh/httpd24/root/usr/sbin/apachectl /opt/rh/httpd24/root/usr/sbin/fcgistarter /opt/rh/httpd24/root/usr/sbin/htcacheclean /opt/rh/httpd24/root/usr/sbin/httpd /opt/rh/httpd24/root/usr/sbin/rotatelogs /opt/rh/httpd24/root/usr/sbin/suexec ``` The other paths worth knowing: ```text /opt/rh/httpd24/root/etc/httpd/conf/httpd.conf main config /opt/rh/httpd24/root/etc/httpd/conf.d/ extra config, ssl.conf /opt/rh/httpd24/root/etc/httpd/conf.modules.d/ LoadModule lines /opt/rh/httpd24/root/usr/lib64/httpd/modules/ the 2.4 modules /opt/rh/httpd24/root/var/www/html/ default document root /var/log/httpd24/ logs /etc/rc.d/init.d/httpd24-httpd init script ``` The binaries aren't on your `PATH`. Either use the full path or start a shell with the collection enabled: ```bash scl enable httpd24 bash apachectl -V ``` ## Swap the services Stop 2.2, start 2.4, and make sure only 2.4 comes back after a reboot: ```bash service httpd stop chkconfig httpd off service httpd24-httpd start chkconfig httpd24-httpd on ``` Browse to the server and you should get the 2.4 test page. Don't `yum remove httpd`: Virtualmin, Webmin and a number of other packages depend on it, and you may want to switch back. ## Making Virtualmin use it Virtualmin writes its virtual hosts into `/etc/httpd/conf/httpd.conf`. The quickest way to get 2.4 reading the same config is to replace the collection's config file with a link to the old one: ```bash cd /opt/rh/httpd24/root/etc/httpd/conf mv httpd.conf httpd.conf~24 ln -s /etc/httpd/conf/httpd.conf httpd.conf ``` Then tell Webmin which Apache to drive. In Webmin go to Servers, Apache Webserver, Module Config and set: ```text Apache server root directory /opt/rh/httpd24/root/etc/httpd Path to httpd executable /opt/rh/httpd24/root/usr/sbin/httpd Path to apachectl /opt/rh/httpd24/root/usr/sbin/apachectl Command to start Apache service httpd24-httpd start Command to stop Apache service httpd24-httpd stop Command to apply configuration service httpd24-httpd reload ``` Leave the config file path pointing at `/etc/httpd/conf/httpd.conf` so new virtual servers keep landing in the file 2.4 is now reading. Afterwards run System Settings, Re-Check Configuration in Virtualmin so it picks up the new version number; it writes slightly different directives for 2.4. ## Fixing the 2.2 config This is where the time goes. The 2.2 file won't start under 2.4 as it is. Always test before restarting: ```bash /opt/rh/httpd24/root/usr/sbin/apachectl -t ``` The changes I had to make: ServerRoot and modules. The old file has `ServerRoot "/etc/httpd"` and a block of `LoadModule ... modules/mod_x.so` lines, which resolve to the 2.2 modules. Point `ServerRoot` at `/opt/rh/httpd24/root/etc/httpd`, delete the old `LoadModule` block and pull in the 2.4 one instead. 2.4 also needs an MPM chosen explicitly and a couple of modules that used to be built in. ```apache ServerRoot "/opt/rh/httpd24/root/etc/httpd" Include conf.modules.d/*.conf ``` Access control. `Order`, `Allow` and `Deny` are gone in favour of `Require`: ```apache # 2.2 Order allow,deny Allow from all # 2.4 Require all granted ``` `mod_access_compat` will keep the old syntax working while you convert, but don't mix both styles in one block; the results are hard to predict. Removed and renamed directives: ```text NameVirtualHost remove it, 2.4 ignores it and warns LockFile replaced by Mutex SSLMutex replaced by Mutex MaxClients now MaxRequestWorkers MaxRequestsPerChild now MaxConnectionsPerChild DefaultType remove it ``` PHP. The `mod_php` from the base RHEL 6 PHP 5.3 packages is built against 2.2 and will not load into 2.4. Run PHP through FastCGI instead: Virtualmin's per-domain fcgid mode works once `mod_fcgid` for httpd24 is installed, or use a PHP collection that ships a module for httpd24. The other trap is that you are editing the config of the web server you are connected through, if you manage the box through Webmin. Keep two SSH sessions open: edit in one and test and restart from the other, so a broken config never leaves you without a way back in. Logs now go to `/var/log/httpd24/` for anything not defined per virtual host, so check there when it refuses to start. Today: RHEL 6 left maintenance support in November 2020. If you're still on it, the job is moving the sites to a current release, not upgrading Apache in place.