set interfaces tunnel tun0 address 'xxx'
set interfaces tunnel tun0 description 'xxx
set interfaces tunnel tun0 encapsulation 'ip6gretap'
set interfaces tunnel tun0 multicast 'enable'
set interfaces tunnel tun0 parameters ip ttl '255'
set interfaces tunnel tun0 parameters ipv6 hoplimit '255'
set interfaces tunnel tun0 remote 'xxx'
set interfaces tunnel tun0 source-address 'xxx'
set interfaces tunnel tun0 vrf 'core'

set vrf name core protocols isis interface dum0
set vrf name core protocols isis net '49.0001.1900.0700.0003.00'

set vrf name core protocols isis interface tun0

vyos@vyos# commit
[ vrf name core protocols isis ]
VyOS had an issue completing a command.

We are sorry that you encountered a problem while using VyOS.
There are a few things you can do to help us (and yourself):
- Make sure you are running the latest version of the code available at
  https://downloads.vyos.io/rolling/current/amd64/vyos-rolling-latest.iso
- Consult the forum to see how to handle this issue
  https://forum.vyos.io
- Join our community on slack where our users exchange help and advice
  https://vyos.slack.com

When reporting problems, please include as much information as possible:
- do not obfuscate any data (feel free to contact us privately if your 
  business policy requires it)
- and include all the information presented below

Report Time:      2021-05-05 15:15:21
Image Version:    VyOS 1.4-rolling-202105050912
Release Train:    sagitta

Built by:         autobuild@vyos.net
Built on:         Wed 05 May 2021 08:12 UTC
Build UUID:       78b8bd29-d828-4d2f-9903-d602aaaddcc0
Build Commit ID:  d3e2f3801f3db1

Architecture:     x86_64
Boot via:         installed image
System type:      KVM guest

Hardware vendor:  QEMU
Hardware model:   Standard PC (i440FX + PIIX, 1996)
Hardware S/N:     
Hardware UUID:    d9b6a227-a7cf-4897-9dc5-07aaa9c9b988

Traceback (most recent call last):
  File "/usr/libexec/vyos/conf_mode/protocols_isis.py", line 227, in <module>
    apply(c)
  File "/usr/libexec/vyos/conf_mode/protocols_isis.py", line 209, in apply
    frr_cfg.commit_configuration(isis_daemon)
  File "/usr/lib/python3/dist-packages/vyos/frr.py", line 458, in commit_configuration
    reload_configuration('\n'.join(self.config), daemon=daemon)
  File "/usr/lib/python3/dist-packages/vyos/frr.py", line 206, in reload_configuration
    raise CommitError('FRR configuration failed while running commit. Please ' \
vyos.frr.CommitError: FRR configuration failed while running commit. Please enable debugging to examine logs.

To enable debugging run: "touch /tmp/vyos.frr.debug" and "sudo systemctl stop vyos-configd"



[[vrf name core protocols isis]] failed
Commit failed