ESXI 6.7 Unable to create datastore iSCSI

[Johnathan.Hall]

Hey,

I've managed to setup my FreeNAS server for iSCSI and connect to an ESXI server. The FreeNAS Device shows up but when I go to create a datastore is errors unable to change host config.

FreeNAS Server:

• FreeNAS 11.2-U5
• Intel(R) Core(TM) i7-7700K CPU @ 4.20GHz
• 32Gb RAM
• 16Gb USB - Boot Drive
• 6 x 4TB 5400 SATA WD - RAIDZ2
• 2 port 10G network card

ESXI server is Running ESXI 6.7.0

Just for setup I set one connection from FreeNAS to use DCHP, one connection from ESXI to use DCHP for the Management network, and one connection from ESXI to static for the data connection.

So following some guides on here I've managed to setup on FreeNAS a zvol on the RAID dataset. Setup iSCSI to use the zvol and set the pool to use the DCHP address.
After adding allow the targets an extents in FreeNAS I added the FreeNAS IP as a dynamic target in the iSCSI setup in ESXI. Rescaned and the static targets showed up along with the FreeNAS device. When trying to create a datastore on the FreeNAS iSCSI disk I get the error "Unable to change host config"

The thing I've tried so far are:
- Making sure the block size is set to 512
- Set the MTU to 9000 and the same on both FreeNAS and ESXI, also made sure the switch has jumbo frames enabled.
- Disabled Physical Block Size Reporting
- Changed permission to give write access to everything.

Any insight or help on this would be greatly appreciated.
If you need any more info on the setup or servers let me know.

Thanks,

Johnathan

 

[jgreco]

Don't use DHCP.

Don't use RAIDZ for block storage.

Don't use jumbo frames.

Whoever told you these things - ignore them from here on out, just all bad advice.

Your root failure is jumbo. See https://kb.vmware.com/s/article/2151431

The other things will bite you later on.

 

[Johnathan.Hall]

So upon changing to a static ip for FreeNAS, EXSI can no longer talk to it. I've seen guides that say to set default gateway and some that don't, neither of which works.
FreeNAS has an IP of 10.0.0.1 and ESXI has 10.0.0.2. They are now isolated from everything else it is just ESXI -> Cable -> Switch -> Cable -> FreeNAS. I've add another connection to FreeNAS just so I can manage it.
Both have the same /24 netmask. I'm hoping it is just a miss configured setting.

Changing the MTU to 1500 and disabling Jumbo frames will fix the datastore issue, thanks for the info on that.

What would you recommend instead of RAIDZ for FreeNAS? The plan is once I am able to prove that the connection works then I was going to connect two other ESXI servers to it and run some VMs off it, after upgrading to SSDs though.

 

[jgreco]

When setting up complex things, it's best to do it one step at a time and validate each step was done correctly. Figure out why "ESXi can no longer talk to it." Make sure all the networking is properly configured. Make sure the devices can talk to each other. This generally involves reviewing the switchport settings. Then make sure each device can ping the switch. Then make sure the switch can ping each device. Then make sure the devices can ping each other.

The guides that say you need a default gateway are potentially demonstrating a lack of understanding of networking and are quite possibly just regurgitating setup-by-rote. For a dedicated storage network, you obviously don't need a default gateway. If the network is going to also be talking to other networks (such as the Internet, which is a terrible idea), then it needs a default, and that's another thing you need to include in your reachability testing.

https://www.ixsystems.com/community...d-why-we-use-mirrors-for-block-storage.44068/

 

[Johnathan.Hall]

I got it figured out. Not sure what was messed up or on what end it was.
I just wiped the configs and started over. Ping test worked right away and ESXI found the device and was able to create the datastore.

Yes, I read that thread. Mirrored is definitely the way I'm going to go, probably 3 disk mirror (if cost allows it).

Thanks for the help.

 

[jgreco]

I got it figured out. Not sure what was messed up or on what end it was.

Happens to everyone. I do this stuff professionally, which is why I tend to walk through things slowly and validate each step, and then automate where I can, so mistakes don't happen as easily. Even then, you sometimes end up turning back the dial and re-checking all your work.