make it easier to set up more than 2 VMs for testing

test/Vagrantfile

@@ -1,7 +1,9 @@
 VAGRANTFILE_API_VERSION = "2"
 
-host1_ip = "192.168.48.19" # arbitrary private IP
-host2_ip = "192.168.48.15" # arbitrary private IP
+# these ought to match what is in config.sh
+n_machines = 2
+ip_prefix = "192.168.48"
+ip_suffix_base = 10
 
 def configure_docker(host, ip)
   pkgs = "lxc-docker"
@@ -30,12 +32,11 @@ end
 
 Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|
 
-  config.vm.define "host1" do |host1|
-    configure_docker(host1, host1_ip)
-  end
-
-  config.vm.define "host2" do |host2|
-    configure_docker(host2, host2_ip)
+  (1..n_machines).each do |i|
+    config.vm.define "host#{i}" do |host|
+      ip_suffix = ip_suffix_base + i
+      configure_docker(host, "#{ip_prefix}.#{ip_suffix}")
+    end
   end
 
 end

test/config.sh

@@ -2,11 +2,24 @@
 
 set -e
 
+# these ought to match what is in Vagrantfile
+N_MACHINES=${N_MACHINES:-2}
+IP_PREFIX=${IP_PREFIX:-192.168.48}
+IP_SUFFIX_BASE=${IP_SUFFIX_BASE:-10}
+
+HOSTS=
+for i in $(seq 1 $N_MACHINES); do
+    IP="${IP_PREFIX}.$((${IP_SUFFIX_BASE}+$i))"
+    HOSTS="$HOSTS $IP"
+done
+
+# these are used by the tests
+HOST1="${IP_PREFIX}.$((${IP_SUFFIX_BASE}+1))"
+HOST2="${IP_PREFIX}.$((${IP_SUFFIX_BASE}+2))"
+
 . ./assert.sh
 
 SSH=${SSH:-ssh -l vagrant -i ./insecure_private_key -o UserKnownHostsFile=./.ssh_known_hosts -o CheckHostIP=no -o StrictHostKeyChecking=no}
-HOST1=${HOST1:-192.168.48.19}
-HOST2=${HOST2:-192.168.48.15}
 
 remote() {
     rem=$1

test/setup.sh

@@ -8,7 +8,7 @@ curl -sS https://raw.githubusercontent.com/lehmannro/assert.sh/master/assert.sh
 . ./config.sh
 
 echo Copying weave images and script to hosts
-for HOST in $HOST1 $HOST2; do
+for HOST in $HOSTS; do
     docker_on $HOST load -i /var/tmp/weave.tar
     docker_on $HOST load -i /var/tmp/weavedns.tar
     docker_on $HOST load -i /var/tmp/weavetools.tar