The trailing comments in the config file contain the component version information, which is used by migration scripts. The syntax of the comments have several issues, as mentioned here:
http://wiki.vyos.net/wiki/Migration_scripts#Changing_the_trailing_comment_syntax
The migration script runner rewrite (T1334) put in place the mechanism for using a preferable syntax, which is natively supported by the vyos1x-config, respectively, vyatta-cfg, parsers (commit ea9bee4c9e0a12947027bb83a6bf493cdf1ed1ed in libvyosconfig, before the refactor to vyos1x-config; respectively, commit e4fe8143d9a9d86eafe04fed3cd788659b46f465 in vyatta-cfg).
Current syntax:
```
/* Warning: Do not remove the following line. */
/* === vyatta-config-version: "broadcast-relay@1:cluster@1:config-management@1:conntrack@1:conntrack-sync@1:dhcp-relay@2:dhcp-server@5:dns-forwarding@2:firewall@5:interfaces@4:ipsec@5:l2tp@2:lldp@1:mdns@1:nat@4:ntp@1:pptp@1:qos@1:quagga@4:snmp@1:ssh@1:system@16:vrrp@2:vyos-accel-ppp@2:wanloadbalance@3:webgui@1:webproxy@2:zone-policy@1" === */
/* Release version: 1.3-rolling-202002121701 */
```
New syntax:
```
// Warning: Do not remove the following line.
// vyos-config-version: "broadcast-relay@1:cluster@1:config-management@1:conntrack@1:conntrack-sync@1:dhcp-relay@2:dhcp-server@5:dns-forwarding@2:firewall@5:interfaces@4:ipsec@5:l2tp@2:lldp@1:mdns@1:nat@4:ntp@1:pptp@1:qos@1:quagga@4:snmp@1:ssh@1:system@16:vrrp@2:vyos-accel-ppp@2:wanloadbalance@3:webgui@1:webproxy@2:zone-policy@1"
// Release version: 1.3-rolling-202002121701
```
Two additions will precede the switch:
(1) the migration runner script will run the VirtualMigrator (which updates syntax) before Migrator; though the switch over can be set globally, this is to avoid the need for preprocessing the syntax in configtree.
(2) add --reverse to the VirtualMigrator, in order to restore the old syntax for portability to earlier releases.
and, to consider:
(3) in the pending rewrite to vyatta-save-config.pl, opt to save _both_ config.boot (new syntax) _and_ config.boot.1.2 (old syntax), for portability to previous releases.