The mtx binary requires my tape library to be assigned a sg# driver, but the kernel periodically renumbers the sg devices. Normally, we would write a udev rule to manually assign a persistent name, but it looks like things have changed as I can't seem to get a match on CEntOS7. I'd appreciate any feedback or pointers to help me get my rule working. My two attempts are below.

cat /etc/udev/rules.d/90-local.rules

KERNEL=="sg[0-9]*", SUBSYSTEM=="scsi_generic", \ ENV{ID_SERIAL}=="1QUANTUM_D0H0112430_LLA", SYMLINK+="sg8"

SUBSYSTEM=="scsi", SUBSYSTEMS=="scsi_genric", \ ATTRS{model}=="Scalar i40-i80 ", SYMLINK:="sg8"

Neither rule above generates a match with udev, so I still have something wrong. Right now the assignment is sg7 (but it's had other names in the past.

udevadm info --query=all --name=/dev/sg7 P: /devices/pci0000:00/0000:00:07.0/0000:04:00.0/0000:05:00.0/0000:06:00.1/host8/rport-8:0-0/target8:0:0/8:0:0:1/scsi_generic/sg7 N: sg7 S: tape/by-id/scsi-1QUANTUM_D0H0112430_LLA E: DEVLINKS=/dev/tape/by-id/scsi-1QUANTUM_D0H0112430_LLA E: DEVNAME=/dev/sg7 E: DEVPATH=/devices/pci0000:00/0000:00:07.0/0000:04:00.0/0000:05:00.0/0000:06:00.1/host8/rport-8:0-0/target8:0:0/8:0:0:1/scsi_generic/sg7 E: ID_MODEL=Scalar_i40-i80 E: ID_MODEL_ENC=Scalar\x20i40-i80\x20\x20 E: ID_REVISION=190G E: ID_SCSI=1 E: ID_SCSI_SERIAL=QUANTUMD0H0112430_LLA E: ID_SERIAL=1QUANTUM_D0H0112430_LLA E: ID_SERIAL_SHORT=QUANTUM_D0H0112430_LLA E: ID_TYPE=generic E: ID_VENDOR=QUANTUM E: ID_VENDOR_ENC=QUANTUM\x20 E: MAJOR=21 E: MINOR=7 E: SUBSYSTEM=scsi_generic E: USEC_INITIALIZED=28815292891

Assigned and parent device listed below: udevadm info -a -p `udevadm info -q path -n /dev/sg7`

looking at device '/devices/pci0000:00/0000:00:07.0/0000:04:00.0/0000:05:00.0/0000:06:00.1/host8/rport-8:0-0/target8:0:0/8:0:0:1/scsi_generic/sg7': KERNEL=="sg7" SUBSYSTEM=="scsi_generic" DRIVER==""

looking at parent device '/devices/pci0000:00/0000:00:07.0/0000:04:00.0/0000:05:00.0/0000:06:00.1/host8/rport-8:0-0/target8:0:0/8:0:0:1': KERNELS=="8:0:0:1" SUBSYSTEMS=="scsi" DRIVERS=="ch" ATTRS{rev}=="190G" ATTRS{type}=="8" ATTRS{scsi_level}=="4" ATTRS{model}=="Scalar i40-i80 " ATTRS{state}=="running" ATTRS{unpriv_sgio}=="0" ATTRS{queue_type}=="none" ATTRS{iodone_cnt}=="0xe2" ATTRS{iorequest_cnt}=="0xe2" ATTRS{queue_ramp_up_period}=="120000" ATTRS{device_busy}=="0" ATTRS{evt_capacity_change_reported}=="0" ATTRS{timeout}=="0" ATTRS{evt_media_change}=="0" ATTRS{ioerr_cnt}=="0x7" ATTRS{queue_depth}=="30" ATTRS{vendor}=="QUANTUM " ATTRS{evt_soft_threshold_reached}=="0" ATTRS{device_blocked}=="0" ATTRS{evt_mode_parameter_change_reported}=="0" ATTRS{evt_lun_change_reported}=="0" ATTRS{evt_inquiry_change_reported}=="0" ATTRS{dh_state}=="detached" ATTRS{iocounterbits}=="32" ATTRS{eh_timeout}=="10"

Would anyone mind pointing out the error in my udev rule or proposing a better way of getting a persistent sg device name?