Hi All, lets continue our useful Junos command series by looking at 2 more interesting commands. One is really a way of doing same thing as in Cisco however 2^nd is completely different command n I doubt available in other vendor CLIs.

We will look at configuration from interface stanza but can be applied to other areas.

So this is our example interface config from one of the interface.

re0.MX104_PE> show configuration interfaces ge-0/0/1
description "Test";
mtu 1600;
hold-time up 0 down 1000;
unit 0 {
 family inet {
 address 10.0.0.170/30;
 }
 family mpls;
}

Now due to any reason the interface which you were using has changed and now you need to put the same config on lets support ge-0/0/3

Lets look at current config of ge-0/0/3

re0.MX104_PE> show configuration interfaces ge-0/0/3
re0.MX104_PE>

As expected, config is empty and nothing has been configured.

Ok to configure the same parameters on new interface, one method is to go n set each configuration stanza individually. i.e..

edit
edit interface ge-0/0/3
set description “Test”
etc etc…

which is valid method but time consuming. Junos gives us facility to do the same thing by using command “copy”

Using this command, you can copy the config from one interface to another without going through all those lengthy steps.

re0.MX104_PE> edit
Entering configuration mode
[edit]
re0.MX104_PE# copy interfaces ge-0/0/1 to ge-0/0/3

[edit]
re0.MX104_PE# show | compare
[edit interfaces]
+ ge-0/0/3 {
+ description "Test";
+ mtu 1600;
+ hold-time up 0 down 1000;
+ unit 0 {
+ family inet {
+ address 10.0.0.170/30;
+ }
+ family mpls;
+ }
+ }


re0.MX104_PE# delete interfaces ge-0/0/1

re0.MX104_PE# show | compare
[edit interfaces]
- ge-0/0/1 {
- description "Test";
- mtu 1600;
- hold-time up 0 down 1000;
- unit 0 {
- family inet {
- address 10.0.0.170/30;
- }
- family mpls;
- }
- }
+ ge-0/0/3 {
+ description "Test";
+ mtu 1600;
+ hold-time up 0 down 1000;
+ unit 0 {
+ family inet {
+ address 10.0.0.170/30;
+ }
+ family mpls;
+ }
+ }

So you can see this has made the configuration easy to move.

Only catch here is that target interface in which you want to copy the configuration should be totally empty of any configuration otherwise you will see error like this.

re0.MX104_PE# copy interfaces ge-0/0/1 to ge-0/0/3
error: target statement 'ge-0/0/3' already exists

Ok so that’s was one command

Lets move over to next command which is similar to Cisco or might be to other vendors but most of the Juniper engineers are not aware of this.

This is to delete the whole interface config and put that into default mode.

In Cisco IOS, we would be doing something like default interface <interface name> under config mode to put the config into default config.

In Juniper to achieve the same thing, you need to either delete individual statements under interface config or you can just mention delete at the top interface level which would prompt you for confirmation and will delete everything.

[edit]
re0.MX104_PE# edit interfaces ge-0/0/1

[edit interfaces ge-0/0/1]
re0.MX104_PE# show
description "Test";
mtu 1600;
hold-time up 0 down 1000;
unit 0 {
 family inet {
 address 10.0.0.170/30;
 }
 family mpls;
}

[edit interfaces ge-0/0/1]
re0.MX104_PE# delete
Delete everything under this level? [yes,no] (no) yes

[edit interfaces ge-0/0/1]
re0.MX104_PE# show | compare
[edit interfaces ge-0/0/1]
- description "Test";
- mtu 1600;
- hold-time up 0 down 1000;
- unit 0 {
- family inet {
- address 10.0.0.170/30;
- }
- family mpls;
- }

Only difference is that in Cisco using “default”, there will still be configuration present under interface like “no ip address” etc etc however in Junos, this will delete everything under it.

So that’s all, I hope you liked this article as well and will make use of these commands in your day to day operational work or troubleshooting.

Regards

Mohit Mittal