My Qubes OS crashed and My Qubes can't run, I need to your two help!

I don’t english speaker, this help is written by Lingva translate, if English is unnatural, please forgive me.

My Qubes OS crashed, so I challanged to repair it, but I don’t understand two issue.
All Qubeses don’t become to run, error message is “Qube sys-firewall has failed to start: Multiple VGs found with the same name: skipping qubes_dom0
Use --selelt vg_uuid= in place of the VG name.”
I discovered issue of like it on this forum, I type it in Dom0 Terminal “qvm-pci detach -v sys-firewall dom0:00_1f.6”, but error message appeared "qvm-pci: error: backend vm ‘dom0’ doesn’t expose device ‘00_1f.6’ ".

So I buy new PC, I install Qubes it, and I challanged to move old Qubes data.
But Qubes of old Qubes can’t run, I can’t backup to My Qubes and datas in it, what do I?

Next, I add HDD as second pool on old Qubes OS.
I must move to Qubes on this HDD pool, I must not crash this HDD pool and Qubes, so I need to mount this HDD to new Qubes OS.
How do I it?

Do you have two Qubes OS installed on the same machine (on the same disk or on different disk) without using disk encryption?
Or did you create secondary storage as described here:

But used the same qubes_dom0 VG name that is used by your primary Qubes OS storage?

Thank you!

1th error issue is two Qubes OS install in one pc.
I can normally run new Qubes OS.

And I challange to mount HDD as 2nd storage in old Qubes OS.
I enter this command in dom0 terminal:

qvm-pool --add <pool_name> lvm_thin -o volume_group=<vg_name>,thin_pool=<thin_pool_name>,revisions_to_keep=2

I success mount HDD to new Qubes OS as 2nd storage.
But qvm-clone command don’t run:

qvm-clone -P <pool_name>
qvm-clone: error: no such domain:

I check by sudo lvs, I can discover old Qubes names.
But my used Qubes in old Qubes OS aren’t auto indicate in new Qubes OS.
I must use old Qubes, how do I?

I guess you need to somehow disable the LVM auto-activation on your other Qubes OS partition.
Maybe you need to edit the udev rules to exclude your other PV:
Related issue:

What do you mean?

I have succeeded in removing the old SSD what installed old Qubes OS and launching one new Qubes OS normally.
The first problem has been solved.

When I used old Qubes OS SSD, I added HDD as second pool.
I must use this HDD on my new Qubes OS, my desire is old second pool using on my new Qubes OS.
Why is there issue of volume group’s default name or exclude PV on second pool (or HDD)?

I got it now, that you can run the old and new Qubes OS separately without a problem by disconnecting disks.
Regarding your secondary storage issue:
You can’t just use the secondary storage pool configured in old Qubes OS in your new Qubes OS.
You’ll have to backup the qubes from your secondary storage in the old Qubes OS, recreate the secondary storage in new Qubes OS and then restore the qubes from backup to the secondary storage pool: