in reference to this forum thread: https://forum.vyos.io/t/failed-config-migration-from-v1-2-3-to-1-2-rolling-201911030217/4322/8
I just tried to upgrade a very simple VyOS 1.2.3-LTS labor instance to 1.2-rolling-201911030217. Config migration failed with this console output:
```
[ 20.983324] vyos-router[1090]: Started watchfrr.
[ 20.996641] vyos-router[1090]: Mounting VyOS Config...done.
[ 21.112754] vyos-router[1090]: Starting VyOS router: migrateTraceback (most recent call last):
[ 21.120689] vyos-router[1090]: File "/opt/vyatta/etc/config-migrate/migrate/dns-forwarding/0-to-1", line 38, in <module>
[ 21.133234] vyos-router[1090]: config = ConfigTree(config_file)
[ 21.137767] vyos-router[1090]: File "/usr/lib/python3/dist-packages/vyos/configtree.py", line 175, in __init__
[ 21.144921] vyos-router[1090]: raise ValueError("Failed to parse config: {0}".format(msg))
[ 21.152688] vyos-router[1090]: ValueError: Failed to parse config: lexing: empty token
[ 21.157479] vyos-router[1090]: Called process error: Command '['/opt/vyatta/etc/config-migrate/migrate/dns-forwarding/0-to-1', '/opt/vyatta/etc/config/config.boot']' returned non-zero exit status 1.
[ 44.109480] vyos-router[1090]: rl-system firewall configure failed!
[ 44.487986] vyos-config[1160]: Configuration error
```
show version before update:
```
Version: VyOS 1.2.3
Built by: Sentrium S.L.
Built on: Fri 13 Sep 2019 11:15 UTC
Build UUID: bb328444-2f89-4d39-8dab-068278c09194
Build Commit ID: 24f1a74bc88f3a
Architecture: x86_64
Boot via: installed image
System type: Microsoft Hyper-V guest
Hardware vendor: Microsoft Corporation
Hardware model: Virtual Machine
```
DNS forwarder config before update:
```
dns {
forwarding {
allow-from 127.0.0.1/32
cache-size 0
domain intern {
server 172.16.13.254
}
ignore-hosts-file
listen-address 127.0.0.1
name-server 1.1.1.1
}
```
I also tried update to rolling version 201911040217, same result. The V1.2.3 config is attached as file to this ticket.
I see the same problem on an (not labor) instance of VyOS on AWS with older rolling version (about august) upgrade to current rolling.
If necessairy I can also document the versions and config of this second affected instance.
{F433512}