put comments for custom_ami in Vagrantfiles.

It seems that vagrant-aws plugin can't override `aws.ami` when we set vagrant box which supports was provider.

multinodes/Vagrantfile

@@ -12,6 +12,7 @@ ninfos = gen_node_infos(conf)
 # vagrant-aws, vagrant-berkshelf, vagrant-omnibus, vagrant-hosts, vagrant-cachier
 Vagrant.configure("2") do |config|
   # https://vagrantcloud.com/everpeace/boxes/mesos
+  # If you set custom_ami in aws_config.yaml, please comment out this.
   config.vm.box = "everpeace/mesos"
 
   # enable plugins
@@ -49,6 +50,9 @@ Vagrant.configure("2") do |config|
       end
 
       cfg.vm.provider :aws do |aws, override|
+        # If you set custom_ami in aws_config.yaml, please activate this.
+        # override.vm.box = "dummy"
+        # override.vm.box_url = "https://github.com/mitchellh/vagrant-aws/raw/master/dummy.box"
 
         aws.access_key_id = conf["access_key_id"]
         aws.secret_access_key = conf["secret_access_key"]
@@ -189,6 +193,10 @@ SCRIPT
         end
       end
       cfg.vm.provider :aws do |aws, override|
+        # If you set custom_ami in aws_config.yaml, please activate this.
+        # override.vm.box = "dummy"
+        # override.vm.box_url = "https://github.com/mitchellh/vagrant-aws/raw/master/dummy.box"
+
         aws.access_key_id = conf["access_key_id"]
         aws.secret_access_key = conf["secret_access_key"]
 

multinodes/cluster.yml

@@ -48,7 +48,10 @@ security_groups: ["EDIT_HERE"]     # array of VPN security groups. e.g. ['sg***
 keypair_name: EDIT_HERE
 ssh_private_key_path: EDIT_HERE
 region: EDIT_HERE
+
 # set a custom AMI to use if you need something other than the defaults
+# If you set this, you will have to comment out config.vm.box
+# and activate all override.vm.box and override.vm.box_url in Vagrnatfile.
 #custom_ami: EDIT_HERE
 
 # see http://aws.amazon.com/ec2/instance-types/#selecting-instance-types

standalone/Vagrantfile

@@ -7,6 +7,7 @@ mesos_version = "0.20.0"
 
 Vagrant.configure("2") do |config|
   # https://vagrantcloud.com/everpeace/boxes/mesos
+  # If you set custom_ami in aws_config.yaml, please comment out this.
   config.vm.box = "everpeace/mesos"
 
   # enable plugins
@@ -50,6 +51,10 @@ Vagrant.configure("2") do |config|
 
   conf = YAML.load_file('aws_config.yaml')
   config.vm.provider :aws do |aws, override|
+    # If you set custom_ami in aws_config.yaml, please activate this.
+    # override.vm.box = "dummy"
+    # override.vm.box_url = "https://github.com/mitchellh/vagrant-aws/raw/master/dummy.box"
+
     aws.access_key_id = conf["access_key_id"]
     aws.secret_access_key = conf["secret_access_key"]
 

standalone/aws_config.yaml

@@ -6,7 +6,10 @@ secret_access_key: EDIT_HERE
 # ["ap-northeast-1", "ap-southeast-1", "eu-west-1", "sa-east-1", "us-east-1",
 #  "us-west-1", "ap-southeast-2", "us-west-2"]
 region: us-east-1
+
 # set a custom AMI to use if you need something other than the defaults
+# If you set this, you will have to comment out config.vm.box
+# and activate override.vm.box and override.vm.box_url in Vagrnatfile.
 #custom_ami: EDIT_HERE
 
 # array of security groups. e.g. ['sg*** ']