* Make sure you connect to the correct LUN on the iscsi target. See [[:sanuri]] for the correct URI syntax for specifying the LUN.
  * **Really read the above, and make sure that the LUN number is correct.** It is the actual LUN # and not index of client accessible LUNs.
  * See [[http://forum.ipxe.org/showthread.php?tid=17411#pid33299|this forum post]] about a common confusion about the LUNs number.
  * Use tcpdump or Wireshark to check the iSCSI traffic for what is going wrong. Build iPXE with DEBUG=iscsi might give more details, but a packet dump is likely more useful in this case.