- Introduce "ha_shared" port option, which being set to "on" moves the
port into separate port group, shared between HA nodes. This allows to
better handle cases when iSCSI portals are bound to CARP address that can
dynamically move between nodes. Some initiators (at least VMware) don't
detect that after iSCSI reconnect they've attached to different SCSI port
from different port group, that totally breakes ALUA status parsing.
In theory, I believe, it should be enough to have different iSCSI portal
group tags on different nodes to make initiators detect this condition,
but it seems like VMware ignores those values, and even full LUN retaste
forced by UA does not help.
- Make CTL report up to three port groups: 1 -- non-HA mode or ports
with "ha_shared" option set, 2 -- HA node 1, 3 -- HA node 2.
- Report Transitioning state for all port groups when HA interlink is
connected, but neither of nodes is primary for the LUN.
MFC after: 2 weeks
This change allows to decode respective functions in isp(4) in target mode
and pass them through CAM to CTL. Unfortunately neither CAM nor isp(4)
support returning response info for those task management functions now.
On the other side I just have no initiator to test this functionality.
I am not sure what for it was done. Now open routine should automatically
fall back to read-only if open for writing is impossible. In such case
attempt to upgrade to write sounds strange.
MFC after: 1 week
We allow to modify only few fields in mode pages now, but still it is
not good if they unexpectedly change during failover. Also this fixes
reporting of "Mode parameters changed" UAs on secondary node.
HA protocol requires strict version, parameters and configuration match.
Differences there may cause full set of problems up to kernel panic.
To avoid that, validate peer parameters on connect, and abort connection
immediately if some mismatch detected.
REPORT LUNS command is more related to target rather then specific LUN.
This node may be primary for LUNs for some reason unknown to another,
and command forwarded to another node won't be able to report them.
REQUEST SENSE is related to LUN, but in our implementation it reports
only UAs and CAs, that are stored locally rather then on primary node.
