There is a process already using the admin port 4848

There is a process already using the admin port 4848 -- it probably is another instance of a GlassFish server.
Command start-domain failed.

如果启动glassfish出现这样的错误，请在你电脑里的host文件修改一下，比如我电脑的目录位置为C:\Windows\System32\drivers\etc下

就是它了。

上图写你的IP地址，WEI是我电脑的hostname，就是电脑名称，修改保存后，就可以启动成功了