Take care of the subnet on public subnet

This patch will take care of the subnet on public range. Instead of
having a stoned /24, we can use now use at least /27 subnet (because
foreman will try to use 20 IPs for public floating ip pool)
This is not the best way to do that, but it's better than the current
way.

It also add a parameter to set the number of floating IP we want to use
from the public subnet in provider network.

Change-Id: I467f2a4098d2da3c6f666453cead64e18d0c655c
JIRA: BGS-75
Signed-off-by: arnaudmorin <arnaud.morin@gmail.com>

1 files changed, 24 insertions, 4 deletions

diff --git a/foreman/ci/deploy.sh b/foreman/ci/deploy.sh
index 2ccb64b..edad2a4 100755
--- a/foreman/ci/deploy.sh
+++ b/foreman/ci/deploy.sh
@@ -41,6 +41,7 @@ display_usage() {
   echo -e "\n   -enable_virtual_dhcp : Run dhcp server instead of using static IPs.  Use this with -virtual only. \n"
   echo -e "\n   -static_ip_range : static IP range to define when using virtual and when dhcp is not being used (default), must at least a 20 IP block.  Format: '192.168.1.1,192.168.1.20' \n"
   echo -e "\n   -ping_site : site to use to verify IP connectivity from the VM when -virtual is used.  Format: -ping_site www.blah.com \n"
+  echo -e "\n   -floating_ip_count : number of IP address from the public range to be used for floating IP. Default is 20.\n"
 }
 
 ##find ip of interface
@@ -57,6 +58,16 @@ function find_subnet {
   printf "%d.%d.%d.%d\n" "$((i1 & m1))" "$((i2 & m2))" "$((i3 & m3))" "$((i4 & m4))"
 }
 
+##finds last usable ip (broadcast minus 1) of a subnet from an IP and netmask
+## Warning: This function only works for IPv4 at the moment.
+##params: ip, netmask
+function find_last_ip_subnet {
+  IFS=. read -r i1 i2 i3 i4 <<< "$1"
+  IFS=. read -r m1 m2 m3 m4 <<< "$2"
+  IFS=. read -r s1 s2 s3 s4 <<< "$((i1 & m1)).$((i2 & m2)).$((i3 & m3)).$((i4 & m4))"
+  printf "%d.%d.%d.%d\n" "$((255 - $m1 + $s1))" "$((255 - $m2 + $s2))" "$((255 - $m3 + $s3))" "$((255 - $m4 + $s4 - 1))"
+}
+
 ##increments subnet by a value
 ##params: ip, value
 ##assumes low value
@@ -196,6 +207,10 @@ parse_cmdline() {
                 ping_site=$2
                 shift 2
             ;;
+        -floating_ip_count)
+                floating_ip_count=$2
+                shift 2
+            ;;
         *)
                 display_usage
                 exit 1
@@ -217,6 +232,10 @@ parse_cmdline() {
       exit 1
     fi
   fi
+
+  if [ -z "$floating_ip_count" ]; then
+    floating_ip_count=20
+  fi
 }
 
 ##disable selinux
@@ -717,10 +736,10 @@ configure_network() {
 
       ##we have to define an allocation range of the public subnet to give
       ##to neutron to use as floating IPs
-      ##we should control this subnet, so this range should work .150-200
-      ##but generally this is a bad idea and we are assuming at least a /24 subnet here
       ##if static ip range, then we take the difference of the end range and current ip
       ## to be the allocation pool
+      ##if not static ip, we will use the last 20 IP from the subnet
+      ## note that this is not a really good idea because the subnet must be at least a /27 for this to work...
       public_subnet=$(find_subnet $next_public_ip $public_subnet_mask)
       if [ ! -z "$static_ip_range" ]; then
         begin_octet=$(echo $next_public_ip | cut -d . -f4)
@@ -735,8 +754,9 @@ configure_network() {
           echo "${blue}Neutron Floating IP range: $public_allocation_start to $public_allocation_end ${reset}"
         fi
       else
-        public_allocation_start=$(increment_subnet $public_subnet 150)
-        public_allocation_end=$(increment_subnet $public_subnet 200)
+        last_ip_subnet=$(find_last_ip_subnet $next_public_ip $public_subnet_mask)
+        public_allocation_start=$(increment_subnet $public_subnet $(( $last_ip_subnet - $floating_ip_count )) )
+        public_allocation_end=$(increment_subnet $public_subnet $(( $last_ip_subnet )) )
         echo "${blue}Neutron Floating IP range: $public_allocation_start to $public_allocation_end ${reset}"
         echo "${blue}Foreman VM is up! ${reset}"
       fi