import re


def remove_redundant_path_slashes(path):
    """
    If a relative filename contains multiple consecutive / characters (except at the beginning,
    in case of //server/host paths), remove them.
    >>> remove_redundant_path_slashes('/test//test2')
    '/test/test2'
    >>> remove_redundant_path_slashes('//test///test2')
    '//test/test2'
    >>> remove_redundant_path_slashes('')
    ''
    """
    path_suffix = path[1:]
    path_suffix = re.sub(r'//+', '/', path[1:])
    
    return path[0:1] + path_suffix