When interfaces is added or removed on fly while VOS running on VM, it needs to be rebooted. Otherwise, you will see following error in versa-service.log with continuous vsmd core dumpes:

Deserializing the interface list from /run/vinterfaces
Adding interface eth0
Adding interface eth1
Adding interface eth2
Adding interface eth3
Adding interface eth4
Unable to open file /sys/bus/pci/devices/0000:04:00.0/local_cpus
Unable to open file /sys/bus/pci_express/devices/0000:04:00.0/local_cpus
versa-vsmd: ../usr/sbin/vsm/vsm_common_intf.c:3444: vsm_init_local_cpu_for_desc: Assertion `0' failed.

Back trace of core dumps will be similar to below:

#0  0x00007f42ddfcb737 in raise () from /lib/x86_64-linux-gnu/libpthread.so.0

#0  0x00007f42ddfcb737 in raise () from /lib/x86_64-linux-gnu/libpthread.so.0

#1  <signal handler called>

#2  0x00007f42dab3cf47 in raise () from /lib/x86_64-linux-gnu/libc.so.6

#3  0x00007f42dab3e8b1 in abort () from /lib/x86_64-linux-gnu/libc.so.6

#4  0x00007f42dab2e42a in ?? () from /lib/x86_64-linux-gnu/libc.so.6

#5  0x00007f42dab2e4a2 in __assert_fail () from /lib/x86_64-linux-gnu/libc.so.6

#6  0x000055a2b89ccf50 in vsm_init_local_cpu_for_desc (desc=desc@entry=0x7f42d704ca80) at ../usr/sbin/vsm/vsm_common_intf.c:3444

#7  0x000055a2b89df600 in vsm_interface_fill_inf_desc (vsn_slot=0 '\000') at ../usr/sbin/vsm/vsm_common_intf.c:3626

#8  vsm_interface_subsys_init (evbase=0x7f42d7082000, vcn_ip=0x55a2c429d20c <g_vsboot_cfg+2284> "127.0.0.1", vsn_slot=vsn_slot@entry=0 '\000') at ../usr/sbin/vsm/vsm_common_intf.c:7562

#9  0x000055a2b8a23c6e in vsm_post_init () at ../usr/sbin/vsm/vsm.c:3204

#10 0x000055a2b8a26920 in vsm_main (argc=<optimized out>, argv=<optimized out>) at ../usr/sbin/vsm/vsm.c:2587

#11 0x000055a2b8a2763f in main (argc=6, argv=0x7ffe1753ecf8) at ../usr/sbin/vsm/vsm_main.cpp:11

VOS does not supports adding or deleting interfaces on fly while it is hosted on VM. After adding/deleting interface, reboot the VM.