Using a 32GB USB Flash drive to boot ESXi and works great so far. I have 25GB of free space and was hoping to host FreeNAS or IllumiOS as well, but so far the web utilities won't budge to allow a datastore in the free space. Wondering if this is a new feature of EXSi 6.7 or an imposed limit of USB? I used HDDs that allowed datastore for images and also booted ESXi 5.5. So I'm a bit confused.
ESXi 6.7 - USB Flash to Boot and Datastore?
- Thread starter pc-tecky
- Start date
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This has long been an imposed limit of vSphere ESXi, including in ESXi. Use of USB Drives as Datastores are not recommended, nor supported in any way by VMware. That stated, you can force it by disabling the USBArbitrator Service (so that drives can't be passed through to VMs), and manually partitioning / formatting your USB Drive.
USB Devices as VMFS Datastore in vSphere ESXi 6.5
USB Devices as VMFS Datastore in vSphere ESXi 6.5
If you wanna get tricky you can use vmkfstools and get at the remaining space, google it, you'll find it, if not I can ask a buddy who did this but he DID have sub-par performance/experience trying to host a FreeNAS in this scenario.
I wanted to do this just recently on a Dell R610 that i only added a H310 LSI HBA to and really wanted the HBA to be pass-thru/vt-D to the FreeNAS AIO VM but alas I got into a chicken-in-egg scenario where sure I could have mounted an NFS slice to the hypervisor and laid down FreeNAS there but then where to put it if i passed the HBA through and needed local stg for the FreeNAS to come up once built off NFS and then removed NFS...not cool/gonna play nice. I ended up using the HBA native to vSphere/ESXi and setting up a FreeNAS on that hussl VMFS formatted drive and serving up vdisk for zil/l2arc off that same hussl and a capacity sas disk for the larger vdisk/vmdk that was gonna provide the main space for that pool. Was fine and akin to a Optane 900P setup where you host zil/l2arc vdisks on it and serve up to FreeNAS/name-your-stg-appliance-here. PLP saves the day in this scenario so I wont worry too much, for a buddy lab setup anyways so I believe it will be solid enough.
I wanted to do this just recently on a Dell R610 that i only added a H310 LSI HBA to and really wanted the HBA to be pass-thru/vt-D to the FreeNAS AIO VM but alas I got into a chicken-in-egg scenario where sure I could have mounted an NFS slice to the hypervisor and laid down FreeNAS there but then where to put it if i passed the HBA through and needed local stg for the FreeNAS to come up once built off NFS and then removed NFS...not cool/gonna play nice. I ended up using the HBA native to vSphere/ESXi and setting up a FreeNAS on that hussl VMFS formatted drive and serving up vdisk for zil/l2arc off that same hussl and a capacity sas disk for the larger vdisk/vmdk that was gonna provide the main space for that pool. Was fine and akin to a Optane 900P setup where you host zil/l2arc vdisks on it and serve up to FreeNAS/name-your-stg-appliance-here. PLP saves the day in this scenario so I wont worry too much, for a buddy lab setup anyways so I believe it will be solid enough.
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Been down this road before, short answer is don't waste your time. Pickup a cheap used SSD off ebay and use that as a datastore location to hold freenas then VT-d the HBA to the VM.
I've been just picking up any old 30GB+ SSD for freenas datastore...usually spend <$30 per drive (intel/samsung)....make a manual backup of the freenas config everytime you make a major upgrade. No need for larger SSD's unless you want extra space for other local VM storage...FreeNAS needs <10GB between temp files and the vmdk flat files.