一台Linux服务器的系统错误日志出现大量的“ kernel: NET: Registered protocol family 36”错误信息，如下所示：
Jul 2 05:27:45 xxxxxx kernel: NET: Registered protocol family 36
Jul 2 05:27:45 xxxxxx kernel: NET: Unregistered protocol family 36
Jul 2 05:28:29 xxxxxx kernel: NET: Registered protocol family 36
Jul 2 05:28:29 xxxxxx kernel: NET: Unregistered protocol family 36
Jul 2 05:29:10 xxxxxx kernel: NET: Registered protocol family 36
Jul 2 05:29:10 xxxxxx kernel: NET: Unregistered protocol family 36
Jul 2 05:30:02 xxxxxx kernel: NET: Registered protocol family 36
Jul 2 05:30:02 xxxxxx kernel: NET: Unregistered protocol family 36
搜索了一下，Syslog being flooded with kernel "NET: Registered protocol family 38" messages. 与 Syslog being flooded with kernel "NET: Registered protocol family 38" messages. 这两篇文章都反馈，由于Linux运行在VMWare虚拟化环境下，安装了vmware-tools，将vmware-tools从10.0.5.-1 升级到10.1.0 就会解决这个问题。摘抄部分内容如下
Situation
Following a round of patching, it was observed that syslog was flooded with the following messages :
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Nov 10 12:08:21 server kernel: [26068249.154815] NET: Unregistered protocol family 38
Nov 10 12:08:21 server kernel: [26068249.154832] NET: Registered protocol family 38
Nov 10 12:08:21 server kernel: [26068249.190805] NET: Unregistered protocol family 38
Nov 10 12:08:23 server kernel: [26068251.200546] NET: Registered protocol family 38
Nov 10 12:08:23 server kernel: [26068251.218140] NET: Unregistered protocol family 38
Nov 10 12:08:23 server kernel: [26068251.218157] NET: Registered protocol family 38
Nov 10 12:08:23 server kernel: [26068251.238126] NET: Unregistered protocol family 38
Nov 10 12:08:23 server kernel: [26068251.238150] NET: Registered protocol family 38
Nov 10 12:08:23 server kernel: [26068251.266167] NET: Unregistered protocol family 38
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Resolution
The servers were running in a VMWare virtualized environment, and installed with the vmware-tools package from VMWare.
Updating the vmware-tools from version 10.0.5-1, to vmware-tools version 10.1.0 resolved the problem.
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其实我们系统的错误日志跟这个基本类似，除了Registered protocol family不同 ，那些链接里面是Registered protocol family是38 ，而我们错误日志中Registered protocol family为 36，检查这个协议发现为XTP协议。
# vmware-toolbox-cmd -v
10.0.0.50046 (build-3000743)
# cat /etc/protocols
官方文档Large number of "NET: Registered protocol family 30 31 36" messages，也有更全面的介绍。结合相关资料判断，这个的确应该是vmware-tools版本引起的。
参考资料：
http://www.novell.com/support/kb/doc.php?id=7018302
https://www.suse.com/support/kb/doc/?id=7018302
https://access.redhat.com/solutions/1518873
