kernel/v2: allow IPs to end in ".1" [GH-2914]

CHANGELOG.md

@@ -62,6 +62,7 @@ BUG FIXES:
     warn of potential issues.
   - core: Synced folders set to the default synced folder explicitly won't
     be deleted. [GH-2873]
+  - core: Static IPs can end in ".1". A warning is now shown. [GH-2914]
   - commands/box: Box add `--force` works with `--provider` flag. [GH-2757]
   - commands/box: Listing boxes with machine-readable output crash is gone.
   - commands/plugin: Plugin installation will fail if dependencies conflict,

plugins/kernel_v2/config/vm.rb

@@ -495,7 +495,8 @@ module VagrantPlugins
             end
 
             if options[:ip] && options[:ip].end_with?(".1")
-              errors << I18n.t("vagrant.config.vm.network_ip_ends_in_one")
+              machine.ui.warn(I18n.t(
+                "vagrant.config.vm.network_ip_ends_in_one"))
             end
           end
         end

templates/locales/en.yml

@@ -869,8 +869,10 @@ en:
           on Windows, NFS isn't supported. If the problem persists, please
           contact Vagrant support.
         network_ip_ends_in_one: |-
-          Static IPs cannot end in ".1" since that address is always
-          reserved for the router. Please use another ending.
+          You assigned a static IP ending in ".1" to this machine.
+          This is very often used by the router and can cause the
+          network to not work properly. If you the network doesn't work
+          properly, try changing this IP.
         network_ip_required: |-
           An IP is required for a private network.
         network_fp_host_not_unique: |-