block.wipe_volume(mode='pvremove') fails on ubuntu precise

[Wesley Wiedenmeier]

On versions of ubuntu trusty and up, lvmetad keeps a cache of pvscan results. In order to refresh this cache after pvremove has been run, block.wipe_volume therefore uses 'pvscan --cache'. However, on ubuntu precise, lvmetad is not yet present. The pvscan utility does not have a --cache flag. That results in block.wipe_volume stacktracing:

ubuntu@ubuntu:/curtin$ sudo python
Python 2.7.3 (default, Jun 22 2015, 19:33:41)
[GCC 4.6.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from curtin import block
>>> block.wipe_volume('/dev/vdb5', mode='pvremove')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "curtin/block/__init__.py", line 666, in wipe_volume
    util.subp(cmd, rcs=[0, 5], capture=True)
  File "curtin/util.py", line 141, in subp
    return _subp(*args, **kwargs)
  File "curtin/util.py", line 91, in _subp
    cmd=args)
curtin.util.ProcessExecutionError: Unexpected error while running command.
Command: ['pvscan', '--cache']
Exit code: 3
Reason: -
Stdout: ''
Stderr: u"pvscan: unrecognized option '--cache'\n Error during parsing of comma
nd line.\n"

[Scott Moser (smoser)]

This bug is believed to be fixed in curtin in 17.1. If this is still a problem for you, please make a comment and set the state back to New

Thank you.