当我准备打开CA时发现下面的错误：
This operation can be performed only on a computer that is joined to a server farm by users who have permissions in SQL Server to read from the configuration database. To connect this server to the server farm, use the SharePoint Products Configuration Wizard, located on the Start menu in Microsoft SharePoint 2010 Products
非常奇怪的错误信息，因为帐号是有权限的，而且我用的是SP2013，找了半天原因，才发现是下面的DNS没设置：
设置完后，再次打开CA，一切正常：
如果问题还存在，检查下sql server的alias设置，在wfe或app server上，点run，输入cliconfg, 点击 alias tab，看sql server的机器名是不是全名。