[Lustre-discuss] question with mount.lustre truncating device name

[Chad Kerner]

Hello,

      We are trying to get a 1.6.5.1 lustre system up and running.  We 
are using udev to map out our fiber channel devices.

We have the following disk /dev/sdb with the scsi_id below.
[root at abe-io07 ~]# ls_fc_luns
HBA  210000e08b0db5cb  host1
210000e08b0db5cb 0x200200a0b80f4498 1:0:0:0 sdb 3600a0b80000f449700000000487dc46a
[root at abe-io07 ~]

The udev rule looks like this:
[root at abe-io07 ~]# grep "ost_l_01" /etc/udev/rules.d/20-local.rules
BUS="scsi", SYSFS{vendor}="IBM", SYSFS{model}="1742", 
PROGRAM="/sbin/scsi_id -g -u -s /block/%k ", 
RESULT="3600a0b80000f449700000000487dc46a", NAME="disk/fc/fastt6e_0" 
SYMLINK="disk/lustre/ost_l_01"
[root at abe-io07 ~]#

The device is there properly named:
[root at abe-io07 ~]# ll /dev/sdb
brw-------  1 root root 8, 16 Aug  5 07:10 /dev/sdb

[root at abe-io07 ~]# ll /dev/disk/fc/fastt6e_0
brw-rw----  1 root disk 8, 16 Aug  5 12:10 /dev/disk/fc/fastt6e_0

[root at abe-io07 ~]# ll /dev/disk/lustre/ost_l_01
lrwxrwxrwx  1 root root 15 Aug  5 12:12 /dev/disk/lustre/ost_l_01 -> ../fc/fastt6e_0

We did a mkfs.lustre on it and it said it was successful(we used the 
/dev/disk/lustre/ost_l_01 device for the format).  But when we 
try to mount the device we get the following error:

  [root at abe-io07 ~]# mount -v -t lustre 
/dev/disk/lustre/ost_l_01 /lustre/local/ost_l_01
arg[0] = /sbin/mount.lustre
arg[1] = -v
arg[2] = -o
arg[3] = rw
arg[4] = /dev/disk/lustre/ost_l_01
arg[5] = /lustre/local/ost_l_01
source = /dev/disk/lustre/ost_l_01 (/dev/disk/lustre/ost_l_01), target = 
/lustre/local/ost_l_01
options = rw
mounting device /dev/disk/lustre/ost_l_01 at /lustre/local/ost_l_01, 
flags=0 options=device=/dev/disk/lustre/ost_l_01
warning: No such file or directory, device /dev/disk/fc/fastt stat 
failed
/sbin/mount.lustre: unable to set tunables for /dev/disk/lustre/ost_l_01 
(may cause reduced IO performance)mount.lustre: mount 
/dev/disk/lustre/ost_l_01 at /lustre/local/ost_l_01 failed: Input/output 
error
Is the MGS running?
[root at abe-io07 ~]

The warning: ... the device name is getting truncated.

It looks like from mount_lustre.c that any device name that contains a 
numeric digit in the device name will get truncated.

         /* The name of the device say 'X' specified in /dev/X may not
          * match any entry under /sys/block/. In that case we need to
          * match the major/minor number to find the entry under
          * sys/block corresponding to /dev/X */
         dev = real_path + src_len - 1;
         while (dev > real_path) {
                 if (isdigit(*dev))
                         *dev = 0;
                 dev--;
         }

         rc = stat(dev, &stat_buf);
         if (rc) {
                 if (verbose)
                         fprintf(stderr, "warning: %s, device %s stat failed\n",
                                 strerror(errno), dev);
                 return rc;
         }

Was looking for some suggestions on getting around this issue.

Thanks,
Chad