This is expected if the following configuration is not in place, please see below:
In the RN, and confirmed by engineering, only following OS supported (without extensions) (ie: 14.04.02,.03,.04):
• RHEL 7.0/7.1/7.2
• Ubuntu14.04, Ubuntu15.04
The right combination is to choose OS from the list with distro kernel and install mlnx_ofed.
You can also use upstream kernel (the target core is more stable there) instead of mlnx_ofed in order to run isert.
So to clarify:
1) Either Ubuntu 14.04 or 15.04 (no extension) + Mellanox OFED driver.
2) Ubuntu 14.04 or 15.04, upstream Kernel with INBOX driver.
You're saying that Ubuntu 15.10 isn't a supported platform? The MLNX_OFED download page disagrees with you.
In any case, it's not worth the effort. I expect that there's someone out there who actually supports their high performance interconnect on a current OS release ... just not Mellanox.
UB15.10 is supported in MLNX_OFED and so does iSER.
As Sopie mentioned there is a need to add support to iSER target (ib_isert) for this platform as mentioned in the release notes.
TGT is a user space target and I've tried it (on MLNX_OFED-3.3 rc - but it shouldn't matter) and it works for me.
please supply more info on the TGT failures (+ all the steps you made) and I'll try to help.