造成此种问题的原因有多种,目前列下我所遇到过的.
1, sshfs usrname@172.23.65.122:/home/usrname ./122
在ubunutu 里面使用 sshfs 命令 映射网络上的文件系统时（samba）到本地时遇到read: Connection reset by peer 问题，
利用 sudo sshfs usrname@172.23.65.122:/home/usrname ./122 ,root权限去映射的话，虽然不会报错，但是映射后，只能用root权限去
访问，其他用户无法访问。
xxx@xxx-Lenovo:~$ sshfs usrname@172.23.65.122:/home/usrname ./122
read: Connection reset by peer
xxx@xxx-Lenovo:~$
解决办法：sudo sshfs -o allow_other yanhd@172.23.65.122:/home/yanhd ./122
添加 -o allow_other参数，允许其他用户访问即可。
2, ssh 使用问题。
ssh -v username@172.23.65.122 ，登录远程server 时，报下列错误WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!
xxx@xxx-Lenovo:~/122$ ssh -v username@172.23.65.122
OpenSSH_5.9p1 Debian-5ubuntu1.1, OpenSSL 1.0.1 14 Mar 2012
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug1: Connecting to 172.23.65.122 [172.23.65.122] port 22.
debug1: Connection established.
debug1: identity file /home/xxx/.ssh/id_rsa type -1
debug1: identity file /home/xxx/.ssh/id_rsa-cert type -1
debug1: identity file /home/xxx/.ssh/id_dsa type -1
debug1: identity file /home/xxx/.ssh/id_dsa-cert type -1
debug1: identity file /home/xxx/.ssh/id_ecdsa type -1
debug1: identity file /home/xxx/.ssh/id_ecdsa-cert type -1
debug1: Remote protocol version 2.0, remote software version OpenSSH_6.2p2 Ubuntu-6
debug1: match: OpenSSH_6.2p2 Ubuntu-6 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.9p1 Debian-5ubuntu1.1
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-ctr hmac-md5 none
debug1: kex: client->server aes128-ctr hmac-md5 none
debug1: sending SSH2_MSG_KEX_ECDH_INIT
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: RSA 91:65:a8:61:d3:54:eb:6b:b5:a8:07:df:d4:e7:77:27
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@ 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 a host key has just been changed.
The fingerprint for the RSA key sent by the remote host is
91:65:a8:61:d3:54:eb:6b:b5:a8:07:df:d4:e7:77:27.
Please contact your system administrator.
Add correct host key in /home/xxx/.ssh/known_hosts to get rid of this message.
Offending RSA key in /home/xxx/.ssh/known_hosts:1
remove with: ssh-keygen -f "/home/xxx/.ssh/known_hosts" -R 172.23.65.122
RSA host key for 172.23.65.122 has changed and you have requested strict checking.
Host key verification failed.
可能是由于远程server 的用户信息更新，之前已经在本地成功登录过，sever端用户信息更新，如密码变更后，再次登录可能会报此问题。
解决方法 ：sudo mv /home/xxx/.ssh/known_hosts /tmp
备注，以上“xxx” 为本机用户名
3, 服务器,可能出问题了,重启服务器解决问题.