创建本地仓库与github的传输
这里假设你的仓库地址为/user/test.git，email地址为youremail@example.com，使用的时候替换成你自己的地址即可。首先注册github帐号，由于你的本地Git仓库和github仓库之间的传输是通过SSH加密的，所以需要使用ssh key：
1）创建SSH Key。在用户主目录下，看看有没有.ssh目录，如果有，再看看这个目录下有没有id_rsa和id_rsa.pub这两个文件，如果有的话，直接跳过此如下命令，如果没有的话，打开命令行，输入如下命令：
# ssh-keygen -t rsa -b 4096 -C "youremail@example.com"
id_rsa是私钥，不能泄露出去，id_rsa.pub是公钥，可以放心地告诉任何人。
2）通过ssh-agent来管理密钥
这里我们通过ssh-agent来管理密钥，ssh-agent是一个密钥管理器，运行ssh-agent以后，使用ssh-add将私钥交给ssh-agent保管，其他程序需要身份验证的时候可以将验证申请交给ssh-agent来完成整个认证过程。
# eval "$(ssh-agent -s)"
# ssh-add –l
4096 7d:8c:84:86:95:ce:47:29:d4:9b:39:8e:28:0c:62:c9 /root/.ssh/id_rsa (RSA)
3）登录github，打开”settings”中的SSH Keys页面，然后点击“Add SSH Key”，填上任意title，在Key文本框里黏贴id_rsa.pub文件的内容。
同步仓库并解决403报错
这时候对本地仓库和github进行同步
# git push -u origin master
error: The requested URL returned error: 403 Forbidden while accessing https://github.com/user/test.git/info/refs
fatal: HTTP request failed
提示403 Forbidden！
打开开关看详细日志
# export GIT_CURL_VERBOSE=1
# git push
* Couldn't find host github.com in the .netrc file; using defaults
* About to connect() to github.com port 443 (#0)
* Trying 192.30.253.112... * Connected to github.com (192.30.253.112) port 443 (#0)
* Initializing NSS with certpath: sql:/etc/pki/nssdb
* CAfile: /etc/pki/tls/certs/ca-bundle.crt
CApath: none
* SSL connection using TLS_RSA_WITH_AES_128_CBC_SHA
* Server certificate:
* subject: CN=github.com,O="GitHub, Inc.",L=San Francisco,ST=California,C=US,postalCode=94107,STREET="88 Colin P Kelly, Jr Street",serialNumber=5157550,incorporationState=Delaware,incorporationCountry=US,businessCategory=Private Organization
* start date: Mar 10 00:00:00 2016 GMT
* expire date: May 17 12:00:00 2018 GMT
* common name: github.com
* issuer: CN=DigiCert SHA2 Extended Validation Server CA,OU=www.digicert.com,O=DigiCert Inc,C=US
> GET /user/test.git/info/refs?service=git-receive-pack HTTP/1.1
User-Agent: git/1.7.1
Host: github.com
Accept: */*
Pragma: no-cache
* The requested URL returned error: 401 Authorization Required
* Closing connection #0
* Couldn't find host github.com in the .netrc file; using defaults
* About to connect() to github.com port 443 (#0)
* Trying 192.30.253.112... * Connected to github.com (192.30.253.112) port 443 (#0)
* CAfile: /etc/pki/tls/certs/ca-bundle.crt
CApath: none
* SSL connection using TLS_RSA_WITH_AES_128_CBC_SHA
* Server certificate:
* subject: CN=github.com,O="GitHub, Inc.",L=San Francisco,ST=California,C=US,postalCode=94107,STREET="88 Colin P Kelly, Jr Street",serialNumber=5157550,incorporationState=Delaware,incorporationCountry=US,businessCategory=Private Organization
* start date: Mar 10 00:00:00 2016 GMT
* expire date: May 17 12:00:00 2018 GMT
* common name: github.com
* issuer: CN=DigiCert SHA2 Extended Validation Server CA,OU=www.digicert.com,O=DigiCert Inc,C=US
> GET /user/test.git/info/refs HTTP/1.1
User-Agent: git/1.7.1
Host: github.com
Accept: */*
Pragma: no-cache
* The requested URL returned error: 403 Forbidden
* Closing connection #0
error: The requested URL returned error: 403 Forbidden while accessing https://github.com/user/test.git/info/refs
fatal: HTTP request failed
可以看到上面红色加粗的文字（The requested URL returned error: 401 Authorization Required），是权限问题导致的，可以修改.git/config文件追加用户名和密码：
1）编辑.git/config文件
2）在[remote “origin”]下找到找到url变量
3）修改url = https://github.com/user/test.git，修改为url = ssh://git@github.com/user/test.git，修改完了保存
4）通过git push origin master进行同步，已经可以成功了