------- Comment From thorsten.di...@de.ibm.com 2016-04-15 13:18 EDT------- Meanwhile, with kernel 4.4.0-18 and installler version 447, the situation is different: While the problem originally occured in installer, is happens now, when the target system is being IPLed.
The "switch" (to avoid the word "reason") is the kernel module scsi_dh_alua. When scsi_dh_alua is loaded, the auto LUN scanning upon activating a zfcp device with NPIV LUNs causes that not all LUNs are detected. I assume, that not the kernel module itself is the problem, but t seems to trigger the problem. A very easy way to reproduce this is as follows: have a system installed with kernel 4.4.0-18 (almost GA). Have two NPIV enabled zfcp adaptors (on different PCHIDs) that can access the same (few) LUNs each. Then: root@s8330005:~# lscss |grep 1732/03 0.0.1905 0.0.0012 1732/03 1731/03 80 80 ff 60000000 00000000 0.0.1945 0.0.0013 1732/03 1731/03 80 80 ff 61000000 00000000 root@s8330005:~# lsmod |grep scsi_dh root@s8330005:~# chccwdev -e 1905 Setting device 0.0.1905 online Done root@s8330005:~# lszfcp -D 0.0.1905/0x50050763070845e3/0x4082405300000000 0:0:0:1079197826 0.0.1905/0x50050763070845e3/0x4083405300000000 0:0:0:1079197827 0.0.1905/0x50050763070845e3/0x4084405300000000 0:0:0:1079197828 0.0.1905/0x50050763070845e3/0x4085405300000000 0:0:0:1079197829 root@s8330005:~# lsmod |grep scsi_dh root@s8330005:~# modprobe scsi_dh_alua root@s8330005:~# chccwdev -e 1945 Setting device 0.0.1945 online Done root@s8330005:~# lszfcp -D 0.0.1905/0x50050763070845e3/0x4082405300000000 0:0:0:1079197826 0.0.1905/0x50050763070845e3/0x4083405300000000 0:0:0:1079197827 0.0.1905/0x50050763070845e3/0x4084405300000000 0:0:0:1079197828 0.0.1905/0x50050763070845e3/0x4085405300000000 0:0:0:1079197829 0.0.1945/0x50050763071845e3/0x4082405300000000 1:0:0:1079197826 /sbin/lszfcp: line 244: /sys/bus/ccw/drivers/zfcp/0.0.1945/host1/rport-1:0-0/target1:0:0/1:0:0:1079197827//hba_id: No such file or directory /sbin/lszfcp: line 245: /sys/bus/ccw/drivers/zfcp/0.0.1945/host1/rport-1:0-0/target1:0:0/1:0:0:1079197827//wwpn: No such file or directory /sbin/lszfcp: line 246: /sys/bus/ccw/drivers/zfcp/0.0.1945/host1/rport-1:0-0/target1:0:0/1:0:0:1079197827//fcp_lun: No such file or directory 0.0.1945/0x50050763071845e3/0x4082405300000000 1:0:0:1079197827 root@s8330005:~# When a zfcp attached SCSI LUN is used for installation, (almost?) all scsi_dh modules are loaded upon activation of the zfcp device. This causes some LUNs not to be detected. If I get acces to that system an blacklist the scsi_dh_alua module, the IPL works as expected ( i.e. all the LUNS are detected properly). -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1567602 Title: FCP devices are not detected correctly nor deterministically To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-z-systems/+bug/1567602/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
