You get the following in your Gateway’s System Logs: Array contains a disk which is not compatible for RAID.
In 5.5 and higher firmware, installed drives are now checked for the enabled Error Recovery Control feature to promote optimal RAID compatibility.
If you are receiving the warning "Array contains a disk which is not compatible for RAID", the HDD model installed in your appliance is likely not an enterprise HDD or capable of utilizing error recovery control. You may utilize this drive and it will likely continue to function in the CTERA appliance but this configuration will be unsupported. On firmware greater than 5.5.197 the use of drives not reporting Error Recovery Control enabled will report in the appliance logs as not compatible for RAID.