Feb 102016
Looking for a way to make a 128GB SSD be enough for several (at least 7) VMs naturally leads to thin provisioned disks. I did not know that LVM can do this and this seems to be the most efficient as well as fastest was to provision disks for VMs.
A nice summary is here and I follow this closely. Here the steps for a plain Debian 8.3 build:
apt-get install thin-provisioning-tools lvcreate -L 50G --thinpool tp_vm giga-vg lvcreate -V 8G --thin -n t_router giga-vg/tp_vm
That’s it. Now giga-vg/t_router is a thin provisioned 8GB volume. To see how full the thin volume pool is:
root@giga:~# lvs LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert root giga-vg -wi-ao---- 22.00g swap_1 giga-vg -wi-ao---- 7.83g t_router giga-vg Vwi-a-tz-- 8.00g tp_vm 0.00 tp_vm giga-vg twi-aotz-- 50.00g 0.00 0.45