This error indicates that the iSCSI target rejected one or more parameters during negotiation.

This should not happen. iPXE explicitly chooses parameter values that cannot meaningfully be rejected (e.g. because they are the RFC-defined default values). However, the iSCSI protocol definition is not wholly internally consistent, and iSCSI targets may differ in their interpretation of the protocol.

Things to try:

• Check the configuration of your iSCSI target to see if it may be rejecting certain parameter values. In particular, check that the target will allow connections that do not use header or data digests.

• Capture a packet trace or build a custom version of iPXE using DEBUG=iscsi to find out precisely which parameter is being rejected.

• If your target is configured to use CHAP authentication, don't forget to set username and password via a call to login.