How to upgrade impala from 2.5 to 2.9? Is ok for just replace the binary？
Any helpful suggestion and links are very welcome^_^
If you're running CDH then you should follow the CDH upgrade process documented here: https://www.cloudera.com/documentation/enterprise/latest/topics/cm_ag_upgrading_cm.html . The exact procedure depends on how you're managing your cluster - with CM or without CM. Cloudera doesn't support upgrading the Impala version independently of the rest of CDH.
When developing Impala we sometimes do manually install Impala onto a cluster by copying over binaries as you describe. However that only works under some circumstances and is not supported or tested by Cloudera.