Re-add 127.0.0.1/8 when bringing down the interfaces

files/image_config/interfaces/interfaces.j2

@@ -26,6 +26,7 @@ iface lo inet loopback
    netmask 255.255.0.0
    scope host
    post-up ip addr del 127.0.0.1/8 dev lo
+   down ip addr add 127.0.0.1/8 dev lo
 {% endblock loopback %}
 {% block mgmt_interface %}
 

src/sonic-config-engine/tests/sample_output/py2/interfaces

@@ -10,6 +10,7 @@ iface lo inet loopback
    netmask 255.255.0.0
    scope host
    post-up ip addr del 127.0.0.1/8 dev lo
+   down ip addr add 127.0.0.1/8 dev lo
 
 # The management network interface
 auto eth0

src/sonic-config-engine/tests/sample_output/py2/interfaces_nomgmt

@@ -10,6 +10,7 @@ iface lo inet loopback
    netmask 255.255.0.0
    scope host
    post-up ip addr del 127.0.0.1/8 dev lo
+   down ip addr add 127.0.0.1/8 dev lo
 
 # The management network interface
 auto eth0

src/sonic-config-engine/tests/sample_output/py2/interfaces_nomgmt_ztp

@@ -10,6 +10,7 @@ iface lo inet loopback
    netmask 255.255.0.0
    scope host
    post-up ip addr del 127.0.0.1/8 dev lo
+   down ip addr add 127.0.0.1/8 dev lo
 
 # The management network interface
 auto eth0

src/sonic-config-engine/tests/sample_output/py2/interfaces_nomgmt_ztp_inband

@@ -10,6 +10,7 @@ iface lo inet loopback
    netmask 255.255.0.0
    scope host
    post-up ip addr del 127.0.0.1/8 dev lo
+   down ip addr add 127.0.0.1/8 dev lo
 
 # The management network interface
 auto eth0

src/sonic-config-engine/tests/sample_output/py2/interfaces_nomgmt_ztp_inband_ip

@@ -10,6 +10,7 @@ iface lo inet loopback
    netmask 255.255.0.0
    scope host
    post-up ip addr del 127.0.0.1/8 dev lo
+   down ip addr add 127.0.0.1/8 dev lo
 
 # The management network interface
 auto eth0

src/sonic-config-engine/tests/sample_output/py2/interfaces_nomgmt_ztp_ip

@@ -10,6 +10,7 @@ iface lo inet loopback
    netmask 255.255.0.0
    scope host
    post-up ip addr del 127.0.0.1/8 dev lo
+   down ip addr add 127.0.0.1/8 dev lo
 
 # The management network interface
 auto eth0

src/sonic-config-engine/tests/sample_output/py2/mvrf_interfaces

@@ -19,6 +19,7 @@ iface lo inet loopback
    netmask 255.255.0.0
    scope host
    post-up ip addr del 127.0.0.1/8 dev lo
+   down ip addr add 127.0.0.1/8 dev lo
 
 # The management network interface
 auto eth0

src/sonic-config-engine/tests/sample_output/py2/mvrf_interfaces_nomgmt

@@ -19,6 +19,7 @@ iface lo inet loopback
    netmask 255.255.0.0
    scope host
    post-up ip addr del 127.0.0.1/8 dev lo
+   down ip addr add 127.0.0.1/8 dev lo
 
 # The management network interface
 auto eth0

src/sonic-config-engine/tests/sample_output/py2/two_mgmt_interfaces

@@ -10,6 +10,7 @@ iface lo inet loopback
    netmask 255.255.0.0
    scope host
    post-up ip addr del 127.0.0.1/8 dev lo
+   down ip addr add 127.0.0.1/8 dev lo
 
 # The management network interface
 auto eth1

src/sonic-config-engine/tests/sample_output/py3/interfaces

@@ -10,6 +10,7 @@ iface lo inet loopback
    netmask 255.255.0.0
    scope host
    post-up ip addr del 127.0.0.1/8 dev lo
+   down ip addr add 127.0.0.1/8 dev lo
 
 # The management network interface
 auto eth0

src/sonic-config-engine/tests/sample_output/py3/interfaces_nomgmt

@@ -10,6 +10,7 @@ iface lo inet loopback
    netmask 255.255.0.0
    scope host
    post-up ip addr del 127.0.0.1/8 dev lo
+   down ip addr add 127.0.0.1/8 dev lo
 
 # The management network interface
 auto eth0

src/sonic-config-engine/tests/sample_output/py3/interfaces_nomgmt_ztp

@@ -10,6 +10,7 @@ iface lo inet loopback
    netmask 255.255.0.0
    scope host
    post-up ip addr del 127.0.0.1/8 dev lo
+   down ip addr add 127.0.0.1/8 dev lo
 
 # The management network interface
 auto eth0

src/sonic-config-engine/tests/sample_output/py3/interfaces_nomgmt_ztp_inband

@@ -10,6 +10,7 @@ iface lo inet loopback
    netmask 255.255.0.0
    scope host
    post-up ip addr del 127.0.0.1/8 dev lo
+   down ip addr add 127.0.0.1/8 dev lo
 
 # The management network interface
 auto eth0

src/sonic-config-engine/tests/sample_output/py3/interfaces_nomgmt_ztp_inband_ip

@@ -10,6 +10,7 @@ iface lo inet loopback
    netmask 255.255.0.0
    scope host
    post-up ip addr del 127.0.0.1/8 dev lo
+   down ip addr add 127.0.0.1/8 dev lo
 
 # The management network interface
 auto eth0

src/sonic-config-engine/tests/sample_output/py3/interfaces_nomgmt_ztp_ip

@@ -10,6 +10,7 @@ iface lo inet loopback
    netmask 255.255.0.0
    scope host
    post-up ip addr del 127.0.0.1/8 dev lo
+   down ip addr add 127.0.0.1/8 dev lo
 
 # The management network interface
 auto eth0

src/sonic-config-engine/tests/sample_output/py3/mvrf_interfaces

@@ -19,6 +19,7 @@ iface lo inet loopback
    netmask 255.255.0.0
    scope host
    post-up ip addr del 127.0.0.1/8 dev lo
+   down ip addr add 127.0.0.1/8 dev lo
 
 # The management network interface
 auto eth0

src/sonic-config-engine/tests/sample_output/py3/mvrf_interfaces_nomgmt

@@ -19,6 +19,7 @@ iface lo inet loopback
    netmask 255.255.0.0
    scope host
    post-up ip addr del 127.0.0.1/8 dev lo
+   down ip addr add 127.0.0.1/8 dev lo
 
 # The management network interface
 auto eth0

src/sonic-config-engine/tests/sample_output/py3/two_mgmt_interfaces

@@ -10,6 +10,7 @@ iface lo inet loopback
    netmask 255.255.0.0
    scope host
    post-up ip addr del 127.0.0.1/8 dev lo
+   down ip addr add 127.0.0.1/8 dev lo
 
 # The management network interface
 auto eth0