Open Fabrics Enterprise Distribution (OFED)
- SRP in OFED 1.5.1 Release Notes
+ SRP in OFED 1.5.2 Release Notes
- March 2010
+ December 2010
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1. Detecting reachable targets
a. To detect all targets reachable by the SRP initiator via the default
- umad device (/dev/umad0), execute the following command:
+ umad device (/dev/infiniband/umad0), execute the following command:
$ ibsrpdm
This command will output information on each SRP target detected, in
You do not see this problem with srp_daemon mode since srp_daemon will
retry to connect.
+- The combination of "weak" single lun srp target, I/O with big block size,
+ default max_command_per_lun=63 while using /dev/urandom to create file with
+ ext3 fs on srp lun, may cause ext3 remount with "read-only" flag
+ ie.
+ Example:
+ sdb1 is first partition of srp lun sdb, ext3 fs is created
+ $ mount /dev/sdb1 /mnt/sdb1; cd /mnt/sdb1
+ $ dd if=/dev/urandom of=10G-file bs=1G count=10
+ --> ext3 fs may remount with read-only flag
+
+ Workarounds:
+ ------------
+ a. Log into the target with small max_command_per_lun (3,4,8)
+ $ echo id_ext=0002c9030008fc0c,ioc_guid=0002c9030008fc0c,
+ dgid=fe800000000000000002c90300084417,max_cmd_per_lun=4,pkey=ffff,
+ service_id=0002c9030008fc0c > /sys/class/infiniband_srp/srp-mlx4_0-1/add_target
+
+ ----------------OR-------------------
+
+ b. Run dd with /dev/zero instead of /dev/urandom
+ $ dd if=/dev/zero of=10G-file bs=1G count=10
+
+ ----------------OR-------------------
+
+ c. Run dd with smaller block size
+ $ dd if=/dev/urandom of=10G-file bs=128K count=40000
+
+ ----------------OR-------------------
+
+ d. Combine the a,b,c steps (This is the recommended workaround)
+
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14. Vendor Specific Notes
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