没有人提问，我来提问吧，大家讨论下

By default, all switches are configured to be VTP servers. This configuration is suitable for small-scale networks in which the size of the VLAN information is small and the information is easily stored in all switches (in NVRAM). In a large network, the network administrator must make a judgment call at some point, when the NVRAM storage that is necessary is wasteful because it is duplicated on every switch. At this point, the network administrator must choose a few well-equipped switches and keep them as VTP servers. Everything else that participates in VTP can be turned into a client. The number of VTP servers should be chosen in order to provide the degree of redundancy that is desired in the network.
这个是文档的原文！
英文文档就是这么说的！www.cisco.com 上有，自己可以去搜索下