If you have erasure coded some directory and perform some operations on the directory you might have observed WARN messages like below
WARN erasurecode.ErasureCodeNative: Loading ISA-L failed: Failed to load libisal.so.2 (libisal.so.2: cannot open shared object file: No such file or directory)
WARN erasurecode.ErasureCodeNative: ISA-L support is not available in your platform... using builtin-java codec where applicable
This WARN messages are due to ISA Library not being present on the node.
If step 6 uses /usr/lib64 directory instead of /lib64, you need copy the .so files in Step 5 to /usr/lib64 directory. Perform the steps on all datanode and namenode hosts or copy the .so files from the above node to /lib64 directories of all other nodes.