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iscsci san on Linux VM and Physical servers

I have two physical server running on Linux and another two physical server which will converted into virtual machine and each of them will host 5 Linux guest OS.
In total I have around 12 Linux OS and all of them will connected to san storage.

My questions is how many port require for me to configure this setup so that all these 12 Linux are connected to the storage ? I think this setup require me around 16port on Ethernet switches but not sure how many port require in storage box
3 Solutions
You should only require at a minimum one NIC per physical device. Your physical servers should be able to share their NIC with all of their VMs. You can of course use more NICs if you wish. Many people like to use more than one NIC for iSCSI for redundant connectivity. If you expect to have really high throughout, you will need more NICs on your SAN.

I have run Hyper-V servers with 50 VMs using two NICs for the iSCSI shared between the host and VMs. Most of my VMs don't connect directly to the SAN, but my Exchange and file servers sure do.
Aaron TomoskyTechnology ConsultantCommented:
Personally I use two nics per host box. One for the San traffic and one for everything else. You can bridge them and run vlans etc but it works well just split San/LAN since my traffic is balanced that way anyway. However I have no redundancy in the event of a nic failure.
nociSoftware EngineerCommented:
Best would be to have two NICs per physical host.

1) for all normal traffic
1) for SAN traffic, preferably in a separate LAN using jumbo frames.

If you want more redundancy/capacity you can use multiple interfaces and make them trunks or separate channels. If you use Trunks fixed setups are prefered to auto-negotiated ones.
I have seen very busy SAN-VLANS fail because the automatic negotiation missed too many negotiation frames, fall back to single lines, and then cause severe flapping of interfaces.
which will cripple IO.
Trunking can only be reliably done using managed switches.

Jumbo frames do not mix well with interfaces that cannot handle them, that's why a separate (V)LAN is preferred. Note that all equipment involved in that (V)LAN must be able to process Jumbo Frames (Servers, switches, SAN's).
Jumbo frames are preferred to get better Throughput of data.
Adjust your I/O size to the jumbo frames (Either 4 or 8K).
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