--- title: "Known Limitations" canonical: "https://docs.infoblox.com/space/NKHOIG/35753636/Known%20Limitations" format: markdown --- vNIOS for KVM supports most of the features of the Infoblox NIOS appliances, with the following limitations: - vNIOS appliances run on virtual hardware. They do not have sensors to monitor the physical CPU temperature, fan speed, and system temperature. - Changing the vNIOS appliance settings through KVM may violate the terms of the vNIOS licensing and support models. The vNIOS appliance may not join the Grid or function properly. - If you get the message` error: Unable to read from monitor: Connection reset by peer` when starting a vNIOS instance in KVM hypervisor, check the memory of the hypervisor. Failure to start an instance may be due to the lack of memory. - At certain times, a power failure (or an unexpected reboot) of the VM host may cause a corruption of the VM guest unless writes are correctly persisted. To do this, you must have an NVRAM-based disk controller on the host system and turn-off disk caching. That is, you must set the value of the `disk_cachemodes` parameter to `writethrough`. - To set the cache mode to `writethrough`, pass the `cache=writethrough` parameter in the `virt-install` command. - To validate this setting in the instance, edit the guest XML file as follows: Configure the cache mode by updating the `cache` parameter inside the `driver` tag to specify a caching option. For example, to set the `cache` parameter to `writethrough`: `` `` `` `` `` `` `>

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