Merge branch '2.9' into stable

cpt-replica.rst

@@ -73,7 +73,7 @@ We suggest the following key parameters:
     there's no need to store it again on the same disk), but caching is
     helpful for the responses to geo api calls. Using a squid is also
     helpful for participating in shared monitoring such as the `WLCG
-    Squid Monitor <http://wlcg-squid-monitor.cern.ch>`.
+    Squid Monitor <http://wlcg-squid-monitor.cern.ch>`_.
 
     Alternatively, separate Squid server machines may be configured in a
     round-robin DNS and each forward to the Apache server, but note that
@@ -91,7 +91,7 @@ We suggest the following key parameters:
     not yet have the files.  Different Stratum 1s should either be
     separately configured on the clients, or a pair can be configured as
     a high availability active/standby pair using the cvmfs-contrib
-    `cvmfs-hastratum1 package <https://github.com/cvmfs-contrib/cvmfs-hastratum1>`.
+    `cvmfs-hastratum1 package <https://github.com/cvmfs-contrib/cvmfs-hastratum1>`_.
     An active/standby pair can also be managed by switching a DNS name
     between two different servers.
 
@@ -102,6 +102,20 @@ We suggest the following key parameters:
     such as ``dnsmasq`` or ``bind``.  We do not recommend ``nscd`` since
     it does not honor the DNS Time-To-Live protocol.  
 
+Apache Configuration
+--------------------
+
+In general the ``cvmfs_server`` utility automatically manages the
+Apache configuration.
+However, for systems based on Red Hat Enterprise Linux 7 it is
+recommended that heavily used Stratum 1s disable the "prefork"
+Multi-Process Module (MPM) and instead use the "worker" or "event"
+MPM which perform much better under heavy load because they work
+with multiple threads per process.
+That can be done by changing which module is uncommented in
+``/etc/httpd/conf.modules.d/00-mpm.conf``.  
+The "event" MPM is the default on Red Hat Enterprise Linux 8.
+
 Squid Configuration
 -------------------
 
@@ -111,15 +125,15 @@ squid called frontier-squid.  It is kept up to date with the latest
 squid bug fixes and has features for easier upgrading and monitoring.
 Step-by-step instructions for setting it up with a Stratum 1 is
 available in the `OSG documentation
-https://opensciencegrid.org/docs/other/install-cvmfs-stratum1/#configuring-frontier-squid`.
+https://opensciencegrid.org/docs/other/install-cvmfs-stratum1/#configuring-frontier-squid`_.
 
 Otherwise, a `squid` package is available in most Linux operating systems.
 The Squid configuration differs from the site-local Squids because the
 Stratum 1 Squid servers are transparent to the clients (*reverse
 proxy*). As the expiry rules are set by the web server, Squid cache
 expiry rules remain unchanged.
 
-The following lines should appear accordingly in /etc/squid/squid.conf:
+The following lines should appear accordingly in ``/etc/squid/squid.conf``:
 
 ::
 
@@ -167,7 +181,7 @@ listens on port 80 by default.  Direct external port 80 traffic to port
 
 If IPv6 is supported, do the same command with ``ip6tables``.  This will
 leave localhost traffic to port 80 going directly to Apache, which is
-good because cvmfs_server uses it that and it doesn't need to go
+good because ``cvmfs_server`` uses that and it doesn't need to go
 through squid.
 
 **Note**: Port 8000 might be assigned to ``soundd``.  On SElinux systems,
@@ -236,7 +250,7 @@ The ``cvmfs_server`` utility reports status and problems to ``stdout``
 and ``stderr``.
 
 For the web server infrastructure, we recommend 
-`cvmfs-servermon <https://github.com/cvmfs-contrib/cvmfs-servermon>`
+`cvmfs-servermon <https://github.com/cvmfs-contrib/cvmfs-servermon>`_
 which watches for problems in every repository's ``.cvmfs_status.json``
 status file.