How to make logical subnets in 1 physical one?

Question

Computer networks

There are 6 devices:
telephones at addresses xx4.1 and xx4.2
Printers at addresses x.x.5.1 and x.x.5.2
And PCs at addresses x.x.6.1 and x.x.6.2
All devices at addresses xxx1 are included in unmanaged switch 1
All devices with addresses xxx2 are included in the unmanaged switch 2
Both switches come in MAIN
There is a MAIN layer 3 switch HPE 1920s A382
The question is: how to make access between ALL devices?

Answer 1

Set the netmask to /16 or less and don't suffer.

Answer 2

Configure routing on the switch.
I have an opinion that the networks are not in vain divided and there is no routing between them - it looks like you are going to lower the network security by your actions.

Answer 3

routing between networks is necessary. Either really make a mask / 16 (255.255.0.0) or install a router in which to raise 3 interfaces xx4.254, xx5.254, and xx6.254, plug them into the switch, and register

route add -net x.x.4.0 netmask 255.255.255.0 gw x.x.4.254
route add -net x.x.5.0 netmask 255.255.255.0 gw x.x.5.254
route add -net x.x.6.0 netmask 255.255.255.0 gw x.x.6.254

accordingly, in each device it will be necessary to register the corresponding GW
. For xx4.1 GW will be xx4.254, etc.
But it's better for you to hike / 16 slap the mask and that's it.