diff --git a/lib/cisco_node_utils/cmd_ref/interface.yaml b/lib/cisco_node_utils/cmd_ref/interface.yaml
index aacab245..49b9b04d 100644
--- a/lib/cisco_node_utils/cmd_ref/interface.yaml
+++ b/lib/cisco_node_utils/cmd_ref/interface.yaml
@@ -127,7 +127,7 @@ hsrp_mac_refresh:
   kind: int
   get_value: '/^hsrp mac-refresh (\d+)$/'
   set_value: '<state> hsrp mac-refresh <timeout>'
-  default_value: false
+  default_value: ~
 
 hsrp_use_bia:
   _exclude: [ios_xr, N5k, N6k]
@@ -137,7 +137,7 @@ hsrp_use_bia:
   # optional match to get the whole config
   get_value: '/^hsrp use-bia(?:\s+\S+\s+\S+)?$/'
   set_value: '<state> hsrp use-bia<scope>'
-  default_value: false
+  default_value: ~
 
 hsrp_version:
   _exclude: [ios_xr, N5k, N6k]
@@ -211,7 +211,7 @@ ipv4_dhcp_relay_src_intf:
   _exclude: [ios_xr]
   get_value: '/^ip dhcp relay source-interface (.*)$/'
   set_value: "<state> ip dhcp relay source-interface <intf>"
-  default_value: false
+  default_value: ~
 
 ipv4_dhcp_relay_subnet_broadcast:
   _exclude: [ios_xr]
@@ -258,7 +258,7 @@ ipv4_proxy_arp:
 ipv4_redirects_loopback:
   kind: boolean
   nexus:
-    default_only: false
+    default_only: ~
   ios_xr:
     get_value: '/^((?:no )?ipv4 redirects)$/'
     set_value: "<state> ipv4 redirects"
@@ -304,7 +304,7 @@ ipv6_dhcp_relay_src_intf:
   _exclude: [ios_xr]
   get_value: '/^ipv6 dhcp relay source-interface (.*)$/'
   set_value: "<state> ipv6 dhcp relay source-interface <intf>"
-  default_value: false
+  default_value: ~
 
 ipv6_redirects:
   _exclude: [ios_xr]
@@ -336,7 +336,7 @@ load_interval_counter_3_delay:
   kind: int
   get_value: '/^load-interval counter 3 (\d+)$/'
   set_value: "<state> load-interval counter 3 <delay>"
-  default_value: false
+  default_value: ~
 
 mtu_loopback:
   kind: boolean
@@ -384,6 +384,7 @@ purge_config:
   set_value:   "default interface <name>"
   get_command: "show running interface"
   get_value:   '/(.*)/'
+  default_value: ~
 
 pvlan_any:
   multiple:
@@ -469,13 +470,13 @@ stp_bpdufilter:
   kind: string
   get_value: '/^spanning-tree bpdufilter (.*)$/'
   set_value: "<state> spanning-tree bpdufilter <filter>"
-  default_value: false
+  default_value: ~
 
 stp_bpduguard:
   kind: string
   get_value: '/^spanning-tree bpduguard (.*)$/'
   set_value: "<state> spanning-tree bpduguard <guard>"
-  default_value: false
+  default_value: ~
 
 stp_cost:
   kind: string
@@ -487,7 +488,7 @@ stp_guard:
   kind: string
   get_value: '/^spanning-tree guard (.*)$/'
   set_value: "<state> spanning-tree guard <guard>"
-  default_value: false
+  default_value: ~
 
 stp_link_type:
   kind: string
@@ -524,7 +525,7 @@ stp_port_type:
   get_command: "show running interface"
   get_value: '/^spanning-tree port type (.*)$/'
   set_value: "<state> spanning-tree port type <type>"
-  default_value: false
+  default_value: ~
 
 stp_vlan_cost:
   multiple:
@@ -632,7 +633,7 @@ switchport_pvlan_trunk_allowed_vlan:
   multiple: true
   get_value: '/^switchport private-vlan trunk allowed vlan (?:add )?(\S+)$/'
   set_value: "switchport private-vlan trunk allowed vlan <range>"
-  default_value: 'none'
+  default_value: none
 
 switchport_pvlan_trunk_association:
   _exclude: [ios_xr, N3k, N3k-F, N9k-F]
@@ -735,7 +736,7 @@ vpc_id:
   kind: int
   get_value: '/^vpc (\d+)$/'
   set_value: '<state> vpc <id>'
-  default_value: false
+  default_value: ~
 
 vpc_peer_link:
   kind: boolean
diff --git a/lib/cisco_node_utils/interface.rb b/lib/cisco_node_utils/interface.rb
index f4fb7719..e2dd3d95 100644
--- a/lib/cisco_node_utils/interface.rb
+++ b/lib/cisco_node_utils/interface.rb
@@ -192,6 +192,7 @@ def pvlan_enable
     # are left untouched.
 
     def access_vlan
+      return nil if switchport_mode == :disabled
       config_get('interface', 'access_vlan', name: @name)
     end
 
@@ -275,6 +276,7 @@ def fabric_forwarding_anycast_gateway
     end
 
     def fabric_forwarding_anycast_gateway=(state)
+      return if fabric_forwarding_anycast_gateway == state
       no_cmd = (state ? '' : 'no')
       config_set('interface',
                  'fabric_forwarding_anycast_gateway',
@@ -325,6 +327,7 @@ def default_hsrp_delay
     end
 
     def hsrp_delay_minimum
+      return nil if switchport_mode != :disabled || @name[/loop/i]
       minimum, _reload = hsrp_delay
       minimum.nil? ? default_hsrp_delay_minimum : minimum
     end
@@ -342,6 +345,7 @@ def default_hsrp_delay_minimum
     end
 
     def hsrp_delay_reload
+      return nil if switchport_mode != :disabled || @name[/loop/i]
       _minimum, reload = hsrp_delay
       reload.nil? ? default_hsrp_delay_reload : reload
     end
@@ -413,6 +417,7 @@ def default_hsrp_use_bia
     end
 
     def hsrp_version
+      return nil if switchport_mode != :disabled || @name[/loop/i]
       config_get('interface', 'hsrp_version', name: @name)
     end
 
@@ -604,6 +609,7 @@ def default_ipv4_dhcp_relay_addr
     end
 
     def ipv4_dhcp_relay_info_trust
+      return nil if @name[/loop/i] || switchport_mode != :disabled
       config_get('interface', 'ipv4_dhcp_relay_info_trust', name: @name)
     end
 
@@ -654,6 +660,7 @@ def default_ipv4_dhcp_relay_src_intf
     end
 
     def ipv4_dhcp_relay_subnet_broadcast
+      return nil if @name[/loop/i] || switchport_mode != :disabled
       config_get('interface', 'ipv4_dhcp_relay_subnet_broadcast', name: @name)
     end
 
@@ -669,6 +676,7 @@ def default_ipv4_dhcp_relay_subnet_broadcast
     end
 
     def ipv4_dhcp_smart_relay
+      return nil if @name[/loop/i] || switchport_mode != :disabled
       config_get('interface', 'ipv4_dhcp_smart_relay', name: @name)
     end
 
@@ -698,6 +706,7 @@ def default_ipv4_forwarding
     end
 
     def ipv4_pim_sparse_mode
+      return nil unless switchport_mode == :disabled
       config_get('interface', 'ipv4_pim_sparse_mode', name: @name)
     end
 
@@ -713,6 +722,7 @@ def default_ipv4_pim_sparse_mode
     end
 
     def ipv4_proxy_arp
+      return nil if @name[/loop/i] || switchport_mode != :disabled
       config_get('interface', 'ipv4_proxy_arp', name: @name)
     end
 
@@ -736,6 +746,7 @@ def ipv4_redirects_lookup_string
     end
 
     def ipv4_redirects
+      return nil unless switchport_mode == :disabled
       config_get('interface', ipv4_redirects_lookup_string, name: @name)
     end
 
@@ -835,6 +846,7 @@ def default_ipv6_dhcp_relay_src_intf
     end
 
     def ipv6_redirects
+      return nil if @name[/loop/i] || switchport_mode != :disabled
       config_get('interface', 'ipv6_redirects', name: @name)
     end
 
@@ -928,6 +940,7 @@ def mtu
     end
 
     def mtu=(val)
+      return if mtu == val
       check_switchport(:disabled)
       config_set('interface', mtu_lookup_string,
                  name: @name, state: '', mtu: val)
@@ -938,6 +951,7 @@ def default_mtu
     end
 
     def speed
+      return nil if @name[/loop|vlan/i]
       config_get('interface', 'speed', name: @name)
     end
 
@@ -950,6 +964,7 @@ def default_speed
     end
 
     def duplex
+      return nil if @name[/loop|vlan/i]
       config_get('interface', 'duplex', name: @name)
     end
 
@@ -973,6 +988,7 @@ def negotiate_auto_lookup_string
     end
 
     def negotiate_auto
+      return nil if @name[/loop|vlan/]
       config_get('interface', negotiate_auto_lookup_string, name: @name)
     end
 
@@ -1047,10 +1063,12 @@ def default_pim_bfd
     end
 
     def storm_control_broadcast
+      return nil if @name[/loop|vlan/i]
       config_get('interface', 'storm_control_broadcast', name: @name)
     end
 
     def storm_control_broadcast=(val)
+      return if val == storm_control_broadcast
       state = val == default_storm_control_broadcast ? 'no' : ''
       level = val == default_storm_control_broadcast ? '' : val
       config_set('interface', 'storm_control_broadcast',
@@ -1062,10 +1080,12 @@ def default_storm_control_broadcast
     end
 
     def storm_control_multicast
+      return nil if @name[/loop|vlan/i]
       config_get('interface', 'storm_control_multicast', name: @name)
     end
 
     def storm_control_multicast=(val)
+      return if val == storm_control_broadcast
       state = val == default_storm_control_multicast ? 'no' : ''
       level = val == default_storm_control_multicast ? '' : val
       config_set('interface', 'storm_control_multicast',
@@ -1077,10 +1097,12 @@ def default_storm_control_multicast
     end
 
     def storm_control_unicast
+      return nil if @name[/loop|vlan/i]
       config_get('interface', 'storm_control_unicast', name: @name)
     end
 
     def storm_control_unicast=(val)
+      return if val == storm_control_broadcast
       state = val == default_storm_control_unicast ? 'no' : ''
       level = val == default_storm_control_unicast ? '' : val
       config_set('interface', 'storm_control_unicast',
@@ -1131,6 +1153,7 @@ def default_stp_bpduguard
     end
 
     def stp_cost
+      return nil if switchport_mode == :disabled
       cost = config_get('interface', 'stp_cost', name: @name)
       cost == 'auto' ? cost : cost.to_i
     end
@@ -1165,6 +1188,7 @@ def default_stp_guard
     end
 
     def stp_link_type
+      return nil if switchport_mode == :disabled
       config_get('interface', 'stp_link_type', name: @name)
     end
 
@@ -1178,6 +1202,7 @@ def default_stp_link_type
     end
 
     def stp_port_priority
+      return nil if switchport_mode == :disabled
       config_get('interface', 'stp_port_priority', name: @name)
     end
 
@@ -1309,6 +1334,7 @@ def switchport_enable(val=true)
 
     # switchport_autostate_exclude is exclusive to switchport interfaces
     def switchport_autostate_exclude
+      return nil if switchport_mode == :disabled
       config_get('interface',
                  'switchport_autostate_exclude', name: @name)
     end
@@ -1399,6 +1425,7 @@ def default_switchport_mode
     end
 
     def switchport_trunk_allowed_vlan
+      return nil if switchport_mode == :disabled
       vlans = config_get('interface', 'switchport_trunk_allowed_vlan',
                          name: @name)
       vlans = vlans.join(',') if vlans.is_a?(Array)
@@ -1421,6 +1448,7 @@ def default_switchport_trunk_allowed_vlan
     end
 
     def switchport_trunk_native_vlan
+      return nil if switchport_mode == :disabled
       config_get('interface', 'switchport_trunk_native_vlan', name: @name)
     end
 
@@ -1457,6 +1485,7 @@ def cli_error_check(result)
     # --------------------------
     # <state> switchport mode private-vlan host
     def switchport_pvlan_host
+      return nil if switchport_mode == :disabled
       config_get('interface', 'switchport_pvlan_host', name: @name)
     end
 
@@ -1473,6 +1502,7 @@ def default_switchport_pvlan_host
     # --------------------------
     # <state> switchport mode private-vlan promiscuous
     def switchport_pvlan_promiscuous
+      return nil if switchport_mode == :disabled
       config_get('interface', 'switchport_pvlan_promiscuous', name: @name)
     end
 
@@ -1665,6 +1695,7 @@ def default_switchport_pvlan_trunk_association
     # --------------------------
     # <state> switchport mode private-vlan trunk promiscuous
     def switchport_pvlan_trunk_promiscuous
+      return nil if switchport_mode == :disabled
       config_get('interface', 'switchport_pvlan_trunk_promiscuous', name: @name)
     end
 
@@ -1681,6 +1712,7 @@ def default_switchport_pvlan_trunk_promiscuous
     # --------------------------
     # <state> switchport mode private-vlan trunk secondary
     def switchport_pvlan_trunk_secondary
+      return nil if switchport_mode == :disabled
       config_get('interface', 'switchport_pvlan_trunk_secondary', name: @name)
     end
 
@@ -1699,6 +1731,7 @@ def default_switchport_pvlan_trunk_secondary
     # Note that range is handled as a string because the entire range is
     # replaced instead of individually adding or removing vlans from the range.
     def switchport_pvlan_trunk_allowed_vlan
+      return nil if switchport_mode == :disabled
       vlans = config_get('interface', 'switchport_pvlan_trunk_allowed_vlan',
                          name: @name)
       vlans = vlans.join(',') if vlans.is_a?(Array)
@@ -1723,6 +1756,7 @@ def default_switchport_pvlan_trunk_allowed_vlan
     # --------------------------
     # <state> switchport trunk native vlan <vlan>
     def switchport_pvlan_trunk_native_vlan
+      return nil if switchport_mode == :disabled
       config_get('interface', 'switchport_pvlan_trunk_native_vlan', name: @name)
     end
 
@@ -1986,10 +2020,12 @@ def default_vpc_id
     end
 
     def vpc_peer_link
+      return nil unless @name[/port-channel/i] && switchport_mode != :disabled
       config_get('interface', 'vpc_peer_link', name: @name)
     end
 
     def vpc_peer_link=(state)
+      return if vpc_peerlink == state
       no_cmd = (state ? '' : 'no')
       config_set('interface', 'vpc_peer_link', name: @name, state: no_cmd)
     end
@@ -2052,8 +2088,14 @@ def purge_config=(val)
     end
 
     def purge_config
+      # This getter is only supported on ethernet interfaces
+      return nil unless @name[/ethernet/]
       state = config_get('interface', 'purge_config', name: @name)
-      state.nil? ? true : false
+      state.nil? ? true : default_purge_config
+    end
+
+    def default_purge_config
+      config_get_default('interface', 'purge_config')
     end
   end  # Class
 end    # Module
diff --git a/lib/cisco_node_utils/interface_DEPRECATED.rb b/lib/cisco_node_utils/interface_DEPRECATED.rb
index 38e46b38..652d9961 100644
--- a/lib/cisco_node_utils/interface_DEPRECATED.rb
+++ b/lib/cisco_node_utils/interface_DEPRECATED.rb
@@ -65,6 +65,7 @@ def switchport_enable_and_mode_private_vlan_host(mode_set)
     end
 
     def switchport_mode_private_vlan_host
+      return nil if switchport_mode == :disabled
       mode = config_get('DEPRECATED',
                         'switchport_mode_private_vlan_host',
                         name: @name)
@@ -299,6 +300,7 @@ def default_switchport_mode_private_vlan_host_promisc
     end
 
     def switchport_mode_private_vlan_trunk_promiscuous
+      return nil if switchport_mode == :disabled
       config_get('DEPRECATED',
                  'switchport_mode_private_vlan_trunk_promiscuous',
                  name: @name)
@@ -331,6 +333,7 @@ def default_switchport_mode_private_vlan_trunk_promiscuous
     end
 
     def switchport_mode_private_vlan_trunk_secondary
+      return nil if switchport_mode == :disabled
       config_get('DEPRECATED',
                  'switchport_mode_private_vlan_trunk_secondary',
                  name: @name)
@@ -361,6 +364,7 @@ def default_switchport_mode_private_vlan_trunk_secondary
     end
 
     def switchport_private_vlan_trunk_allowed_vlan
+      return nil if switchport_mode == :disabled
       result = config_get('DEPRECATED',
                           'switchport_private_vlan_trunk_allowed_vlan',
                           name: @name)
@@ -400,6 +404,7 @@ def default_switchport_private_vlan_trunk_allowed_vlan
     end
 
     def switchport_private_vlan_trunk_native_vlan
+      return nil if switchport_mode == :disabled
       config_get('DEPRECATED',
                  'switchport_private_vlan_trunk_native_vlan',
                  name: @name)