1.ssh登录 The authenticity of host 192.168.0.xxx can't be established. 的问题
用ssh登录一个机器（换过ip地址），提示输入yes后，屏幕不断出现y，只有按ctrl + c结束
错误是：The authenticity of host 192.168.0.xxx can't be established.
以前和同事碰到过这个问题，解决了，没有记录，这次又碰到了不知道怎么处理，还好有QQ聊天记录，查找到一下，找到解决方案：
执行ssh -o StrictHostKeyChecking=no 192.168.0.xxx 就OK
网址是：
http://blog.ossxp.com/2010/04/1026/
记一下，防止又忘记了，又快到3点了，无数个不眠之夜啊。
2011/10/11
某天机器又改IP了，ssh后，报：
mmt@FS01:~$ ssh -o StrictHostKeyChecking=no 192.168.0.130
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that the RSA host key has just been changed.
The fingerprint for the RSA key sent by the remote host is
fe:d6:f8:59:03:a5:de:e8:29:ef:3b:26:6e:3d:1d:4b.
Please contact your system administrator.
Add correct host key in /home/mmt/.ssh/known_hosts to get rid of this message.
Offending key in /home/mmt/.ssh/known_hosts:38
Password authentication is disabled to avoid man-in-the-middle attacks.
Keyboard-interactive authentication is disabled to avoid man-in-the-middle attacks.
Permission denied (publickey,password).
注意这句
Add correct host key in /home/mmt/.ssh/known_hosts to get rid of this message.
执行：
mv /home/mmt/.ssh/known_hosts known_hosts.bak
再连：
ssh -o StrictHostKeyChecking=no 192.168.0.130
OK了!
2.xcrun: error: active developer path ("/Applications/Xcode.app/Contents/Developer/") does not exist, use `xcode-select --switch path/to/Xcode.app` to specify the Xcode that you wish to use for command line developer tools (or see `man xcode-select`)
这个的原因，是因为更新了xcode软件，在更新svn时，找不到这个软件，导致的。
解决办法就是：将Xcode的路径，重新设置一下。
sudo xcode-select --switch “Xcode的path，直接在应用程序里面找到Xcode，拖拽到这里”
