RHEL6 support rpms

Install some rpms required for operation on RHEL6.  Additionally,
remove some system packages that interfere with pip installs.

Change-Id: I273ce59d7bf066e73d524f61b8ad048599101dab
diff --git a/files/rpms/general b/files/rpms/general
index fc3412b..764b602 100644
--- a/files/rpms/general
+++ b/files/rpms/general
@@ -1,14 +1,19 @@
 bridge-utils
 curl
+dbus
 euca2ools # only for testing client
+gcc # dist:rhel6 [2]
 git-core
 openssh-server
 openssl
+libxml2-devel # dist:rhel6 [2]
+libxslt-devel # dist:rhel6 [2]
 psmisc
 pylint
 python-netaddr
 python-pep8
 python-pip
+python-prettytable # dist:rhel6 [1]
 python-unittest2
 python-virtualenv
 screen
@@ -16,3 +21,12 @@
 tcpdump
 unzip
 wget
+
+# [1] : some of installed tools have unversioned dependencies on this,
+# but others have versioned (<=0.7).  So if a later version (0.7.1)
+# gets installed in response to an unversioned dependency, it breaks.
+# This pre-installs a compatible 0.6(ish) version from RHEL
+
+# [2] : RHEL6 rpm versions of python-lxml is old, and has to be
+# removed.  Several tools rely on it, so we install the dependencies
+# pip needs to build it here (see tools/install_prereqs.sh)
\ No newline at end of file
diff --git a/files/rpms/glance b/files/rpms/glance
index 34e3f9a..097cf3f 100644
--- a/files/rpms/glance
+++ b/files/rpms/glance
@@ -1,3 +1,4 @@
+gcc
 libxml2-devel
 python-argparse
 python-devel
diff --git a/stack.sh b/stack.sh
index e192588..d534b87 100755
--- a/stack.sh
+++ b/stack.sh
@@ -525,7 +525,6 @@
 # an error.  It is also useful for following along as the install occurs.
 set -o xtrace
 
-
 # Install Packages
 # ================
 
@@ -546,6 +545,42 @@
     install_quantum_agent_packages
 fi
 
+#
+# System-specific preconfigure
+# ============================
+
+if [[ is_fedora && $DISTRO =~ (rhel6) ]]; then
+    # An old version (2.0.1) of python-crypto is probably installed on
+    # a fresh system, via the dependency chain
+    # cas->python-paramiko->python-crypto (related to anaconda).
+    # Unfortunately, "pip uninstall pycrypto" will remove the
+    # .egg-info file for this rpm-installed version, but leave most of
+    # the actual library files behind in /usr/lib64/python2.6/Crypto.
+    # When later "pip install pycrypto" happens, the built library
+    # will be installed over these existing files; the result is a
+    # useless mess of old, rpm-packaged files and pip-installed files.
+    # Unsurprisingly, the end result is it doesn't work.  Thus we have
+    # to get rid of it now so that any packages that pip-install
+    # pycrypto get a "clean slate".
+    # (note, we have to be careful about other RPM packages specified
+    # pulling in python-crypto as well.  That's why RHEL6 doesn't
+    # install python-paramiko packages for example...)
+    uninstall_package python-crypto
+
+    # A similar thing happens for python-lxml (a dependency of
+    # ipa-client, an auditing thing we don't care about).  We have the
+    # build-dependencies the lxml pip-install will need (gcc,
+    # libxml2-dev & libxslt-dev) in the "general" rpm lists
+    uninstall_package python-lxml
+
+    # If the dbus rpm was installed by the devstack rpm dependencies
+    # then you may hit a bug where the uuid isn't generated because
+    # the service was never started (PR#598200), causing issues for
+    # Nova stopping later on complaining that
+    # '/var/lib/dbus/machine-id' doesn't exist.
+    sudo service messagebus restart
+fi
+
 TRACK_DEPENDS=${TRACK_DEPENDS:-False}
 
 # Install python packages into a virtualenv so that we can track them
@@ -559,7 +594,6 @@
     $DEST/.venv/bin/pip freeze > $DEST/requires-pre-pip
 fi
 
-
 # Check Out and Install Source
 # ----------------------------
 
diff --git a/tools/install_prereqs.sh b/tools/install_prereqs.sh
index 7c4386f..68f11ce 100755
--- a/tools/install_prereqs.sh
+++ b/tools/install_prereqs.sh
@@ -42,7 +42,8 @@
 LAST_RUN=$(head -1 $PREREQ_RERUN_MARKER 2>/dev/null || echo "0")
 DELTA=$(($NOW - $LAST_RUN))
 if [[ $DELTA -lt $PREREQ_RERUN_SECONDS && -z "$FORCE_PREREQ" ]]; then
-    echo "Re-run time has not expired ($(($PREREQ_RERUN_SECONDS - $DELTA)) seconds remaining); exiting..."
+    echo "Re-run time has not expired ($(($PREREQ_RERUN_SECONDS - $DELTA)) seconds remaining) "
+    echo "and FORCE_PREREQ not set; exiting..."
     return 0
 fi