ER Groups Arguments

From Juniper Clue

Problem

Many configuration changes are repeated save for a few bits of information. The 'Groups' command works well for reusing configuration that is repeated, but it is static and must be identical at each place it is applied.

groups {
    copper {
        description "A shiny new 100baseT interface";
        speed 100m;
        link-mode full-duplex;
    }
}
interfaces {
    ge-1/1/9 {
        apply-groups copper;
        unit 0 {
            family inet {
                address 10.10.10.10/24;
            }
        }
   }
}

Besides having to apply many lines of config to make a single routine addition, this method also makes it easy for different users to apply the config in their own 'personal' way, creating inconsistencies.

Solution

Allow the 'groups' command to call 'arguments' that can be used in the group definition by specifying an argument variable.

For example:

groups {
    copper {
        description $1;
        speed 100m;
        link-mode full-duplex;
        unit 0 {
            family inet {
                address $2;
            }
        }
    }
}
interfaces {
    ge-1/1/9 {
        apply-groups copper "Port 1, Bay 2, Rack 3, Room 4" 10.10.10.10/24;
   }
}
interfaces {
    ge-1/1/3 {
        apply-groups copper "Port 15, Bay 2, Rack 3, Room 4" 20.20.20.20/24;
   }
}

The ‘apply-group copper’ line above has two arguments, the first a description, and the second an IP address. They get placed into the group definition where $1 and $2 are, respectively. Due to internal use, $1 may not be a good variable name. Any alternative may be used, i.e. %1, &1, etc.

Preferably syntax checking would look to make sure the number of arguments on the apply-groups command matched the number in the 'groups' definition, and result in a *warning* if they did not match and return a null string for undefined arguments, and ignore excess arguments. This change would not break existing use of the 'groups' and 'apply-groups' commands.