Thank you for the service tag.
You can disable VNC in the iDRAC. Instructions for performing management tasks should be in the manual.
Cipher 0 is enabled by default, so the iDRAC does not require a user/pass when accessed via RACADM or IPMI from the host OS. You can disable cipher 0 via RACADM command. There is a CLI guide in the manual section of the iDRAC page, and there is a security article that has information about cipher 0.
No, you can't upgrade or downgrade an iDRAC. The iDRAC 6 is the only version of the iDRAC that will work in the R310.
Dell EMC, Enterprise Engineer
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