Thanks for your precious info.

I detected my custom network as vmnet3 and I modified as you suggested

answer VNET_3_DHCP no

I verified that dhcp.conf is missing now in  /Library/Preferences/VMware Fusion/vmnet3.

I turned off A machine and I reboot only B machine (client) but I see these logs:

Mar 21 16:18:21 students dhclient: Internet Systems Consortium DHCP Client 4.3.1
Mar 21 16:18:21 students networking[270]: Configuring network interfaces...Internet Systems Consortium DHCP Client 4.3.1
Mar 21 16:18:21 students dhclient: Copyright 2004-2014 Internet Systems Consortium.
Mar 21 16:18:21 students networking[270]: Copyright 2004-2014 Internet Systems Consortium.
Mar 21 16:18:21 students dhclient: All rights reserved.
Mar 21 16:18:21 students networking[270]: All rights reserved.
Mar 21 16:18:21 students dhclient: For info, please visit https://www.isc.org/software/dhcp/
Mar 21 16:18:21 students networking[270]: For info, please visit https://www.isc.org/software/dhcp/
Mar 21 16:18:21 students dhclient:
Mar 21 16:18:21 students dhclient: Listening on LPF/eth0/00:0c:29:26:ea:09
Mar 21 16:18:21 students dhclient: Sending on LPF/eth0/00:0c:29:26:ea:09
Mar 21 16:18:21 students dhclient: Sending on Socket/fallback
Mar 21 16:18:21 students dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 4
Mar 21 16:18:21 students networking[270]: Listening on LPF/eth0/00:0c:29:26:ea:09
Mar 21 16:18:21 students networking[270]: Sending on LPF/eth0/00:0c:29:26:ea:09
Mar 21 16:18:21 students networking[270]: Sending on Socket/fallback
Mar 21 16:18:21 students networking[270]: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 4
Mar 21 16:18:21 students dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 5
Mar 21 16:18:21 students networking[270]: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 5
Mar 21 16:18:21 students dhclient: DHCPREQUEST on eth0 to 255.255.255.255 port 67
Mar 21 16:18:21 students dhclient: DHCPOFFER from 10.0.2.1
Mar 21 16:18:21 students networking[270]: DHCPREQUEST on eth0 to 255.255.255.255 port 67
Mar 21 16:18:21 students networking[270]: DHCPOFFER from 10.0.2.1
Mar 21 16:18:21 students dhclient: DHCPACK from 10.0.2.1
Mar 21 16:18:21 students networking[270]: DHCPACK from 10.0.2.1
Mar 21 16:18:21 students dhclient: bound to 10.0.2.3 -- renewal in 39442 seconds.
Mar 21 16:18:21 students networking[270]: bound to 10.0.2.3 -- renewal in 39442 seconds.
Mar 21 16:18:21 students networking[270]: done.

It like dhcp server was 10.0.2.1, It's always interface of my custom network of Fusion ?

IP address is again assigned as 10.0.2.3. My dhcp server assigns ip address at starting 10.0.2.100

What do you think ?