局域网ssh连接等待时间长的解决方法

在自己局域网连接ssh到自己的小主机服务器上的时候发现执行ssh root@192.168.50.176回车之后，在输入密码之前要等好长一段时间，至少需要十几秒钟。

1、通过ssh -v root@192.168.50.176查看连接详细信息

# ssh -v root@192.168.50.176
OpenSSH_for_Windows_7.7p1, LibreSSL 2.6.5
debug1: Connecting to 192.168.50.176 [192.168.50.176] port 22.
debug1: Connection established.
debug1: identity file C:\\Users\\StaryJie/.ssh/id_rsa type 0
debug1: key_load_public: No such file or directory
debug1: identity file C:\\Users\\StaryJie/.ssh/id_rsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file C:\\Users\\StaryJie/.ssh/id_dsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file C:\\Users\\StaryJie/.ssh/id_dsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file C:\\Users\\StaryJie/.ssh/id_ecdsa type -1
debug1: key_load_public: No such file or directory
debug1: identity file C:\\Users\\StaryJie/.ssh/id_ecdsa-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file C:\\Users\\StaryJie/.ssh/id_ed25519 type -1
debug1: key_load_public: No such file or directory
debug1: identity file C:\\Users\\StaryJie/.ssh/id_ed25519-cert type -1
debug1: key_load_public: No such file or directory
debug1: identity file C:\\Users\\StaryJie/.ssh/id_xmss type -1
debug1: key_load_public: No such file or directory
debug1: identity file C:\\Users\\StaryJie/.ssh/id_xmss-cert type -1
debug1: Local version string SSH-2.0-OpenSSH_for_Windows_7.7
debug1: Remote protocol version 2.0, remote software version OpenSSH_7.4
debug1: match: OpenSSH_7.4 pat OpenSSH* compat 0x04000000
debug1: Authenticating to 192.168.50.176:22 as ‘root‘
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: algorithm: curve25519-sha256
debug1: kex: host key algorithm: ecdsa-sha2-nistp256
debug1: kex: server->client cipher: chacha20-poly1305@openssh.com MAC: <implicit> compression: none
debug1: kex: client->server cipher: chacha20-poly1305@openssh.com MAC: <implicit> compression: none
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: ecdsa-sha2-nistp256 SHA256:2ePNJ/cQW7AIsD+veSBc5XS2xy0kmB3W6Dk3uVnBwDQ
debug1: Host ‘192.168.50.176‘ is known and matches the ECDSA host key.
debug1: Found key in C:\\Users\\StaryJie/.ssh/known_hosts:11
debug1: rekey after 134217728 blocks
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: rekey after 134217728 blocks
debug1: pubkey_prepare: ssh_get_authentication_socket: No such file or directory
debug1: SSH2_MSG_EXT_INFO received
debug1: kex_input_ext_info: server-sig-algs=<rsa-sha2-256,rsa-sha2-512>
debug1: SSH2_MSG_SERVICE_ACCEPT received  # 发现代码跑到这里的时候就卡住了
debug1: Authentications that can continue: publickey,gssapi-keyex,gssapi-with-mic,password
debug1: Next authentication method: publickey
debug1: Offering public key: RSA SHA256:Y5wPUy0NUgYMwwSO4juFhw52YyleflOzomjnNvsokXw C:\\Users\\StaryJie/.ssh/id_rsa
debug1: Authentications that can continue: publickey,gssapi-keyex,gssapi-with-mic,password
debug1: Trying private key: C:\\Users\\StaryJie/.ssh/id_dsa
debug1: Trying private key: C:\\Users\\StaryJie/.ssh/id_ecdsa
debug1: Trying private key: C:\\Users\\StaryJie/.ssh/id_ed25519
debug1: Trying private key: C:\\Users\\StaryJie/.ssh/id_xmss
debug1: Next authentication method: password
debug1: read_passphrase: can‘t open /dev/tty: No such file or directory
root@192.168.50.176‘s password:

2、解决方法

2.1 修改sshd配置文件

[root@staryjie ~]# egrep -v "^#|^$" /etc/ssh/ssh_config
Host *
        ForwardX11Trusted yes
        SendEnv LANG LC_CTYPE LC_NUMERIC LC_TIME LC_COLLATE LC_MONETARY LC_MESSAGES
        SendEnv LC_PAPER LC_NAME LC_ADDRESS LC_TELEPHONE LC_MEASUREMENT
        SendEnv LC_IDENTIFICATION LC_ALL LANGUAGE
        SendEnv XMODIFIERS
SAPIAuthentication  no
UseDNS no
[root@staryjie ~]#

2.2 添加本地电脑iIP到/etc/hosts

[root@staryjie ~]# cat /etc/hosts
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.50.29    windows
[root@staryjie ~]#

2.3 重启sshd

systemctl restart sshd.service

3、查看效果

优化前的速度：

优化之后的速度：

局域网ssh连接等待时间长的解决方法

原文：https://www.cnblogs.com/jie-fang/p/13430884.html