search for: centos6host

I just noticed an interesting behaviour of rup on CentOS5/6: run without any host args, it never prints results for CentOS6 machines. However, if a CentOS6 machine is queried directly, there is a result. It doesnt't matter whether the querying host runs CentOS5 or CentOS6. # rup |grep centos6host # rup centos6host centos6host up 12 days, 19:33, load average: 0.22 0.18 0.11 # With tcpdump, I can see that no rpc requests are issued to the host in the first case. Is there an explanation?