环境：macOS Mojava version 10.14
在更新了Mac OS当前用ssh push 代码到服务器呈现了上面这个谬误。
ssh error: unable to negotiate with IP: no matching cipher found.Their offer: aes256-cbc,aes192-cbc,aes128-cbc...
Unable to negotiate with XX.X.X.XXX port XX: no matching cipher found. Their offer: aes256-cbc,aes192-cbc,aes128-cbcfatal: Could not read from remote repository.Please make sure you have the correct access rightsand the repository exists.呈现谬误的起因是要连贯的代码仓库服务端的ssh版本过低，客户端与服务端的 cipher 没有匹配上，咱们须要在本人的客户端（降级OS后的Mac）从新启用老的 cipher ,这样就能从新建设起连贯了。
具体步骤如下：
第一步：terminal 输出 sudo nano /etc/ssh/ssh_config
atcs-air:~ XXX$ sudo nano /etc/ssh/ssh_config第二步：找到 Ciphers aes128-ctr,aes192-ctr,aes256-ctr,aes128-cbc,3des-cbc，删除这行后面的#号。
# Host *# ForwardAgent no# ForwardX11 no# PasswordAuthentication yes# HostbasedAuthentication no# GSSAPIAuthentication no# GSSAPIDelegateCredentials no# BatchMode no# CheckHostIP yes# AddressFamily any# ConnectTimeout 0# StrictHostKeyChecking ask# IdentityFile ~/.ssh/id_rsa# IdentityFile ~/.ssh/id_dsa# IdentityFile ~/.ssh/id_ecdsa# IdentityFile ~/.ssh/id_ed25519# Port 22# Protocol 2 Ciphers aes128-ctr,aes192-ctr,aes256-ctr,aes128-cbc,3des-cbc# MACs hmac-md5,hmac-sha1,umac-64@openssh.com# EscapeChar ~# Tunnel no# TunnelDevice any:any# PermitLocalCommand no# VisualHostKey no# ProxyCommand ssh -q -W %h:%p gateway.example.com# RekeyLimit 1G 1hHost * SendEnv LANG LC_*第三步：保留 ssh_config 这个文件，退出。而后就能够和以前一样通过ssh连贯代码仓库服务器了。
参考链接：
https://www.itechlounge.net/2...
https://discussions.apple.com...