SIOC or Storage I/O Control is a feature in ESXi which when enabled, it helps the ESXi to monitor datastore latency and throttles the I/O load if the datastore average latency exceeds a particular threshold.
So what is esx_sioc_status_check ?
The NCC health check esx_sioc_status_check verifies if the vSphere feature "Storage I/O Control" (SIOC) settings for both "SIOC" and "SIOC in Stats Mode" are disabled on Nutanix containers.
Why do we want SIOC setting to be disabled in the cluster?
SIOC is an excellent feature for traditional server infrastructure, but it is neither required nor compatible with the Nutanix converged storage architecture. Starting from ESXi 6.0, SIOC in Stats Mode is enabled by default. Nutanix requires that both features be disabled.
It can cause a range of problems in a Nutanix environment and it's highly recommended that we disable it
Want to know more about the issues caused by enabling SIOC and a step-by-step guide as to how to disable it.
Give the following knowledge base article a read which explains the check and the resolution!
Want to know more about vSphere Administration in Nutanix environment
Give the following articles a coffee read!
vSphere Administration Guide
vSphere Networking