set interfaces ethernet eth1 mtu 1500
set interfaces pseudo-ethernet peth1 source-interface eth1
set interfaces pseudo-ethernet peth1 mtu 9000

Traceback (most recent call last):
  File "/usr/libexec/vyos/conf_mode/interfaces-pseudo-ethernet.py", line 89, in <module>
    apply(c)
  File "/usr/libexec/vyos/conf_mode/interfaces-pseudo-ethernet.py", line 81, in apply
    p.update(peth)
  File "/usr/lib/python3/dist-packages/vyos/ifconfig/interface.py", line 1253, in update
    self.set_mtu(config.get('mtu'))
  File "/usr/lib/python3/dist-packages/vyos/ifconfig/interface.py", line 357, in set_mtu
    return self.set_interface('mtu', mtu)
  File "/usr/lib/python3/dist-packages/vyos/ifconfig/control.py", line 184, in set_interface
    return self._set_command(self.config, name, value)
  File "/usr/lib/python3/dist-packages/vyos/ifconfig/control.py", line 109, in _set_command
    return self._command_set[name].get('format', lambda _: _)(self._cmd(cmd))
  File "/usr/lib/python3/dist-packages/vyos/ifconfig/control.py", line 51, in _cmd
    return cmd(command, self.debug)
  File "/usr/lib/python3/dist-packages/vyos/util.py", line 161, in cmd
    raise OSError(code, feedback)
FileNotFoundError: [Errno 2] failed to run command: ip link set dev peth2 mtu 9000
returned:
exit code: 2