On Sat, Feb 12, 2022 at 9:21 AM Glen Jarvis <glen@glenjarvis.com> wrote:
I would like to know why "vdsm-tool config-lvm-filter" makes you pull your hair out.
It was designed to help people configure their system correctly without pulling their hair out trying to understand how lvm filter works, and avoid the many wrong ways it can be used.
Honestly, it is just from a lack of understanding of what is happening when it does break (as it is for us when doing a hypervisor install on a fresh box). Normally, I can just dig through the stack and figure out what is happening. There are enough areas where I don't have some foundations that I'm not able to do so here (yet).
For example, I don't quite understand iSCSI, Multipath, etc enough to know what is breaking, and why.
I'm accustomed to being able to dig deeper at each level until I can generally see what is breaking.
This confusion will go away as I get a bit more experience and have a "map" of what is going on on this level.
FWIW, I started reading the Libvirt book previously mentioned and it's pretty straight forward. It looks like I just need to get through this enough to get a good foothold so that I can figure out how to either fix things when they break or point out properly why something is breaking (so I can get the appropriate help).
Do you have some specific areas you would like to improve?
Actually, yes :) In: 1. Learn libvirt more (in progress)
2. Review source for vdsm-tool to have a better sense what is going on
3. Setup an iSCSI system so that I can make luns, build a system, play with storage pools this way
You may find vdsm/contrib/target tool useful: https://github.com/oVirt/vdsm/blob/master/contrib/target This tool makes it simple to create or delete a new iSCSI target for development purposes. The best way to add iSCSI server for development, is to create a new VM - virt-manager is the easier way to do this, and install targetcli and copy vdsm/contrib/target to the vm. Then to create a new target you can run: # ./target create mytarget Creating target target_name: mytarget target_iqn: iqn.2003-01.org.alpine.mytarget target_dir: /target/mytarget lun_count: 10 lun_size: 100 GiB cache: False exists: False Create target? [N/y]: You may find the tool source interesting, explaining why we configure the target in a certain way. Nir