Do VMs on host Server need physical connectivity to external shared storage (iSCSI)
Hi everyone.
In my lab setup I am using 4 Servers (S1, S2, S3 & S4) and external shared storage (hpe MSA 2040). Now I made S1 as my self-hosted engine and S2 is HA for my RHV-Manager running on S1. Remaining two servers (S3 and S4) are my additional hosts adding to S1 for spawning VMs.
Now my query is:
-> Do I need to connect (Physically) S3 and S4 servers to my shared storage? If 'yes' why?
-> If I spawn VMs on S3 and S4, where do these VM configuration data stored?

Thanks
Responses
You will need a data storage domain (on the MSA 2040) to accommodate the templates and disks of the VM's. The admin portal on the hosted engine supports the following storage types: NFS, POSIX compliant FS, GlusterFS, iSCSI and Fibre Channel. The need for physical connection depends upon the selected storage type.
What do you mean with VM configuration data? The RHV meta data of VM's is stored in the local postgres database running inside the hosted engine. The configuration of the VM itself is on it's disk (on the data storage domain).
According to: http://searchstorage.techtarget.com/definition/iSCSI
iSCSI, which stands for Internet Small Computer System Interface, works on top of the Transport Control Protocol (TCP) and allows the SCSI command to be sent end-to-end over local-area networks (LANs)
S3 and S4 need a TCP connection to the MSA2040 (using their existing networking). Go to the admin portal of the hosted engine and add hosts S3 and S4. This will configure your hosts and a wrong configuration will be result in a failed addition and give you a clue about what is missing.
Yes, you need a connection between the MSA2040 and S3/S4. The hosts use this connection to access the data storage domain containing the templates and disks of the VM's.
When the MSA2040 and S3/S4 are in the same network, you should be fine and adding the hosts via the admin portal should establish the logical connection with the MSA 2040.
You configure the NFS- or iSCSI-path of a storage domain in the RHV-manager and that merely stores a string in the RHV database, it does not access the storage domain itself. When you add a hypervisor, the RHV-manager transfers this path to the hypervisor and the hypervisor itself will access the path.
When S1 and S2 use a separate network to access the MSA and this network is not accessible by S3 and S4, they will not be able to access the MSA.
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