I am new in that area and have some problems with my hadoop cluster.
I fixed many health issues but health of my hosts is still "concerning" (still yellow and not "green", unfortunately). Can this depend on the fact that my hosts are connected through an old switch with a speed of 100 Mbps? Network cards of almost all servers support 1000 Mbps. In the recommendation for resolving this error, it's was advised checking the duplex options. It would have "concerning health" if the all of my hosts working on half-duplex mode, but i've check it and they all have full-duplex mode.
Screen of Network Interface speed issue:
About Cluster installation options that i choose (if need): 1) Use Packages; 2) CDH5; 3) CDH 5.13.0.
P.S. How much does "concerning health" of hosts affect their work? Can I run complex tasks on them? I've just used the test WordCount and calculating the Pi - and they were successful.
These are just warnings, which appear as per the configuration. Nothing to bother about. You can simply supress them and continue working.