wow, that was much smoother than i thought it would be. I guess setting things up the way i have ahead of time was a good thing. now to move on to the rest of life. (also an interesting idea to set up a desktop/laptop this way to see how life works) lvm> vgs VG #PV #LV #SN Attr VSize VFree System 2 1 0 wz--n- 1.02t 1.38g lvm> pvs PV VG Fmt Attr PSize PFree /dev/sda3 System lvm2 a-- 117.38g 1.38g /dev/sdb2 System lvm2 a-- 922.20g 0 lvm> lvs LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert System System Cwi-aoC--- 922.20g [cache] [System_corig] 0.00 0.70 0.00 On Fri, Jul 8, 2016 at 11:24 AM, Stephen Partington wrote: > ​The biggest issue i have is that i am working with a mac mini. the 1T > drive is a 5400 rpm drive. this has been my home server for a while running > server 2016, but it is time to put something more useful on it. > > Part of this is specifically to learn how to use lvm and lvmcache.​ And > ram is on the list for this server just not in the budget yet. > > I am not worried about catastrophic failure or the like as nothing lives > on this server that does not already live anywhere else. > > I did the install with the Ubuntu server install so i could at least get > lvm set up partly ahead of time. so it looks like I am in a good place. I > was reading that article as i received your email. > > So now to extend the vg create the cache and meta lv's and turn things on. > > lvm> pvscan > PV /dev/sdb2 VG System lvm2 [922.20 GiB / 0 free] > PV /dev/sda3 lvm2 [117.38 GiB] > Total: 2 [1.02 TiB] / in use: 1 [922.20 GiB] / in no VG: 1 [117.38 GiB] > lvm> pvs > PV VG Fmt Attr PSize PFree > /dev/sda3 lvm2 --- 117.38g 117.38g > /dev/sdb2 System lvm2 a-- 922.20g 0 > lvm> vgs > VG #PV #LV #SN Attr VSize VFree > System 1 1 0 wz--n- 922.20g 0 > lvm> vgdisplay > --- Volume group --- > VG Name System > System ID > Format lvm2 > Metadata Areas 1 > Metadata Sequence No 2 > VG Access read/write > VG Status resizable > MAX LV 0 > Cur LV 1 > Open LV 1 > Max PV 0 > Cur PV 1 > Act PV 1 > VG Size 922.20 GiB > PE Size 4.00 MiB > Total PE 236082 > Alloc PE / Size 236082 / 922.20 GiB > Free PE / Size 0 / 0 > > > On Fri, Jul 8, 2016 at 11:02 AM, Matt Graham wrote: > >> On 2016-07-08 10:00, Stephen Partington wrote: >> >>> 1T spinning disk and 128G SSD installed. [...] going with LVM-Cache >>> Sadly the Ubuntu server installation does not have the option of >>> setting up LVM for anything other than its most basic configuration >>> >> >> LVM is complicated, and using LVM-cache is a bit more complicated than >> just making some PVs and putting them into a VG and then making LVs. >> >> What I understand about LVM is that you can build your LVM group and >>> then migrate/expand it without a full install/wipe or 3rd disk device >>> to host your core os installation. Can this be done for LVM cache as >>> well? >>> >> >> Yes. Your setup would be something like this: 2 PVs, one on the fast >> disk, one on the slow disk[0]. One VG with both PVs in it. Multiple LVs. >> One named root on the fast disk (mounted at / obviously), one small one >> named cache-meta on the fast disk, one larger one named cache on the fast >> disk, and finally one larger one named origin on the slow disk. You'd >> probably mount the last one on /data or /home or wherever makes sense to >> put the large amount of stuff you want to serve up. I suppose you could >> put / on the spinny-disk and use almost all of the SSD for cache too. Your >> call. >> >> If you already have some PVs and LVs set up, you might need to use pvmove >> and lvresize and resize2fs to resize filesystems and LVs and move them to >> the appropriate PV. These things are of course doable from a running >> system and should not cause any problems. >> >> https://rwmj.wordpress.com/2014/05/22/using-lvms-new-cache-feature/ >> describes all the commands you'd need to run to make this stuff happen. >> And getting an additional 4G or 8G of RAM might help more than using an SSD >> as a cache, depending on what exactly is going on. >> >> (I haven't actually tried this, but I've got a 32G unused partition on my >> SSD right now, and this could be a fun weekend project. I will let you >> know if I run into any problems.) >> >> [0] With 1T disks as cheap as they are, consider a softRAID-1 instead of >> a single spinny disk. Disk failures are No Fun At All. >> >> -- >> Crow202 Blog: http://crow202.org/wordpress >> There is no Darkness in Eternity >> But only Light too dim for us to see. >> --------------------------------------------------- >> PLUG-discuss mailing list - PLUG-discuss@lists.phxlinux.org >> To subscribe, unsubscribe, or to change your mail settings: >> http://lists.phxlinux.org/mailman/listinfo/plug-discuss >> > > > > -- > A mouse trap, placed on top of your alarm clock, will prevent you from > rolling over and going back to sleep after you hit the snooze button. > > Stephen > > -- A mouse trap, placed on top of your alarm clock, will prevent you from rolling over and going back to sleep after you hit the snooze button. Stephen