5_paramiko_SSHException Invalid requirement, parse error at

• 不加sleep(0.5)会出现SSHException: Invalid requirement, parse error at ” ” “问题，原因暂时未知。

• 1. 如果不使用多线程，则不会出现问题
• 1. 使用多线程一定要sleep(0.2)，也就是多个线程之间一定要有时间间隙

#!/usr/bin/env pythonimport paramikoimport threadingimport sysimport timedef ssh(host, user, cmd):    ssh = paramiko.SSHClient()    ssh.set_missing_host_key_policy( paramiko.AutoAddPolicy() )    pkey_file = '/Users/icq/.ssh/id_rsa'    # key = paramiko.RSAKey.from_private_key_file( pkey_file, password='' )    key = paramiko.RSAKey.from_private_key_file( pkey_file, password='' )    try:        ssh.connect( hostname=host, username=user, pkey=key, timeout=5 )    except:        print 'connection has some problems...'        return -1    stdin, stdout, stderr = ssh.exec_command( cmd )    stdout = stdout.read()    stderr = stderr.read()    if stdout:        print '%s: %s' % (host, stdout),        ssh.close()    else:        print '%s: %s' % (host, stderr),        ssh.close()if __name__ == '__main__':    hosts = ['192.168.31.114', '192.168.31.115', '192.168.31.116', '192.168.31.117']    try:        cmd = sys.argv[1]    except IndexError:        print '%s follow a command must be' % __file__        sys.exit(-1)    for host in hosts:        t = threading.Thread( target=ssh, args=(host, 'root', 'uptime') )        t.start()        time.sleep(0.5) #如果不加此行则会出现下面描述的异常        # ssh(host, 'root', 'uptime')执行结果如下，有时候就没有异常，有时候就有 ，我网在也找不到合适的结论，麻烦都是您帮忙看下，这个问题是什么原因导致的呢。192.168.31.116:  11:51:53 up  1:03,  1 user,  load average: 0.07, 0.26, 0.18192.168.31.114:  11:51:53 up  1:03,  1 user,  load average: 0.07, 0.26, 0.18192.168.31.115:  11:51:53 up  1:03,  1 user,  load average: 0.07, 0.26, 0.18Exception in thread Thread-3:Traceback (most recent call last):  File "/Users/icq/.pyenv/versions/2.7.13/lib/python2.7/threading.py", line 801, in __bootstrap_inner    self.run()  File "/Users/icq/.pyenv/versions/2.7.13/lib/python2.7/threading.py", line 754, in run    self.__target(*self.__args, **self.__kwargs)  File "parallel.py", line 12, in ssh    key = paramiko.RSAKey.from_private_key_file( pkey_file, password='' )  File "/Users/icq/.pyenv/versions/2.7.13/lib/python2.7/site-packages/paramiko/pkey.py", line 196, in from_private_key_file    key = cls(filename=filename, password=password)  File "/Users/icq/.pyenv/versions/2.7.13/lib/python2.7/site-packages/paramiko/rsakey.py", line 46, in __init__    self._from_private_key_file(filename, password)  File "/Users/icq/.pyenv/versions/2.7.13/lib/python2.7/site-packages/paramiko/rsakey.py", line 174, in _from_private_key_file    self._decode_key(data)  File "/Users/icq/.pyenv/versions/2.7.13/lib/python2.7/site-packages/paramiko/rsakey.py", line 186, in _decode_key    raise SSHException(str(e))SSHException: Invalid requirement, parse error at "''"192.168.31.117:  11:51:54 up  1:03,  1 user,  load average: 0.07, 0.25, 0.18192.168.31.115:  11:51:54 up  1:03,  1 user,  load average: 0.07, 0.25, 0.18192.168.31.114:  11:51:54 up  1:03,  1 user,  load average: 0.07, 0.25, 0.18192.168.31.115:  11:51:55 up  1:03,  1 user,  load average: 0.07, 0.25, 0.18192.168.31.116:  11:51:55 up  1:03,  1 user,  load average: 0.07, 0.25, 0.18192.168.31.114:  11:51:55 up  1:03,  1 user,  load average: 0.07, 0.25, 0.18192.168.31.117:  11:51:55 up  1:03,  1 user,  load average: 0.07, 0.25, 0.18