na verdade, acabei de perceber que, ao usar um cabo usb3 e conectar a uma porta usb2 no laptop, o dispositivo é encontrado e todas as partições são montadas automaticamente.
O problema que tive anteriormente poderia ser do cabo usb2, que poderia carregar apenas menos energia do que um dispositivo usb3 necessário.
/dev/sdb5 on /media/r/3c45f792-1630-4866-8a33-1534c115f285 type ext4 (rw,nosuid,nodev,uhelper=udisks2)
/dev/sdb6 on /media/r/ce13cd6c-57bd-4beb-b489-10e2aa2a7876 type ext4 (rw,nosuid,nodev,uhelper=udisks2)
/dev/sdb1 on /media/r/SYSTEM type fuseblk (rw,nosuid,nodev,allow_other,default_permissions,blksize=4096)
/dev/mapper/vgroup1-mymedia on /media/r/dc1afac9-27cc-4f76-95a6-91f0ac0060ef type ext4 (rw,nosuid,nodev,uhelper=udisks2)
/dev/mapper/vgroup1-virtualization on /media/r/c71ff7a8-bfee-48e1-9ab1-25e6a8ecd829 type ext4 (rw,nosuid,nodev,uhelper=udisks2)
kernel: [13587.330014] sdb: sdb1 sdb2 sdb3 sdb4 < sdb5 sdb6 sdb7 sdb8 >
kernel: [13587.333642] sd 8:0:0:0: [sdb] Attached SCSI disk
kernel: [13589.035776] EXT4-fs (sdb5): mounted filesystem with ordered data mode. Opts: (null)
kernel: [13589.038729] EXT4-fs (sdb6): mounted filesystem with ordered data mode. Opts: (null)
kernel: [13592.827240] bio: create slab <bio-1> at 1
kernel: [13595.524660] EXT4-fs (dm-0): mounted filesystem with ordered data mode. Opts: (null)
kernel: [13598.882851] EXT4-fs (dm-1): mounted filesystem with ordered data mode. Opts: (null)