Merge pull request #1318 from wk/resolve-dns

Introduce resolve_dns knob (closes #599)

4 files changed, 54 insertions, 9 deletions

diff --git a/docs/Configuration.md b/docs/Configuration.md
index 1d16c91..aea5e3c 100644
--- a/docs/Configuration.md
+++ b/docs/Configuration.md
@@ -214,3 +214,13 @@ next_adds_job: true
 ```
 
 This will allow for a more timely fetch of the device configuration.
+
+## Disabling DNS resolution
+
+In some instances it might not be desirable to attempt to resolve names of nodes. One such use case is when nodes are accessed through an SSH proxy, where the remote end resolves the names differently than the host on which Oxidized runs would.
+
+Names can instead be passed verbatim to the input:
+
+```yaml
+resolve_dns: false
+```
diff --git a/lib/oxidized/config.rb b/lib/oxidized/config.rb
index 9eb9b90..36d9d73 100644
--- a/lib/oxidized/config.rb
+++ b/lib/oxidized/config.rb
@@ -20,6 +20,7 @@ module Oxidized
       asetus.default.username      = 'username'
       asetus.default.password      = 'password'
       asetus.default.model         = 'junos'
+      asetus.default.resolve_dns   = true # if false, don't resolve DNS to IP
       asetus.default.interval      = 3600
       asetus.default.use_syslog    = false
       asetus.default.debug         = false
diff --git a/lib/oxidized/node.rb b/lib/oxidized/node.rb
index 27bd9a5..4105da0 100644
--- a/lib/oxidized/node.rb
+++ b/lib/oxidized/node.rb
@@ -15,7 +15,8 @@ module Oxidized
       ip_addr, _ = opt[:ip].to_s.split("/")
       Oxidized.logger.debug 'IPADDR %s' % ip_addr.to_s
       @name           = opt[:name]
-      @ip             = IPAddr.new(ip_addr).to_s rescue nil
+      @ip             = @name unless Oxidized.config.resolve_dns?
+      @ip           ||= IPAddr.new(ip_addr).to_s rescue nil
       @ip           ||= Resolv.new.getaddress @name
       @group          = opt[:group]
       @input          = resolve_input opt
diff --git a/spec/input/ssh_spec.rb b/spec/input/ssh_spec.rb
index 3c33cd8..0a3bd8d 100644
--- a/spec/input/ssh_spec.rb
+++ b/spec/input/ssh_spec.rb
@@ -8,17 +8,19 @@ describe Oxidized::SSH do
     Oxidized::Node.any_instance.stubs(:resolve_repo)
     Oxidized::Node.any_instance.stubs(:resolve_input)
     Oxidized::Node.any_instance.stubs(:resolve_output)
-    @node = Oxidized::Node.new(name: 'example.com',
-                               input: 'ssh',
-                               output: 'git',
-                               model: 'junos',
-                               username: 'alma',
-                               password: 'armud',
-                               vars: { ssh_proxy: 'test.com' })
   end
 
   describe "#connect" do
-    it "should use proxy command when proxy host given" do
+    it "should use proxy command when proxy host given and connect by ip if resolve_dns is true" do
+      Oxidized.config.resolve_dns = true
+      @node = Oxidized::Node.new(name: 'example.com',
+                                 input: 'ssh',
+                                 output: 'git',
+                                 model: 'junos',
+                                 username: 'alma',
+                                 password: 'armud',
+                                 vars: { ssh_proxy: 'test.com' })
+
       ssh = Oxidized::SSH.new
 
       model = mock
@@ -39,5 +41,36 @@ describe Oxidized::SSH do
       ssh.instance_variable_set("@exec", true)
       ssh.connect(@node)
     end
+
+    it "should use proxy command when proxy host given and connect by name if resolve_dns is false" do
+      Oxidized.config.resolve_dns = false
+      @node = Oxidized::Node.new(name: 'example.com',
+                                 input: 'ssh',
+                                 output: 'git',
+                                 model: 'junos',
+                                 username: 'alma',
+                                 password: 'armud',
+                                 vars: { ssh_proxy: 'test.com' })
+
+      ssh = Oxidized::SSH.new
+
+      model = mock
+      model.expects(:cfg).returns('ssh' => [])
+      @node.expects(:model).returns(model).at_least_once
+
+      proxy = mock
+      Net::SSH::Proxy::Command.expects(:new).with("ssh test.com -W %h:%p").returns(proxy)
+      Net::SSH.expects(:start).with('example.com', 'alma',  port:      22,
+                                                            timeout:   Oxidized.config.timeout,
+                                                            paranoid:  Oxidized.config.input.ssh.secure,
+                                                            keepalive: true,
+                                                            proxy:     proxy,
+                                                            password: 'armud',
+                                                            number_of_password_prompts: 0,
+                                                            auth_methods: %w[none publickey password])
+
+      ssh.instance_variable_set("@exec", true)
+      ssh.connect(@node)
+    end
   end
 end