[LU-2896] IR enabled MGS don't able to register old OST

• Status: Resolved
• Project: Lustre
• Affects Version/s: Lustre 2.3.0, Lustre 2.4.0
• Fix Version/s: Lustre 2.4.0
• Type: Bug
• Priority: Blocker
• Reporter: Alexey Lyashkov
• Assignee: James Nunez (Inactive)
• Resolution: Fixed
• Labels: LB, patch

Environment

OST 2.1, MGS 2.1+ported IR patch.

• Severity: 3

Description

Xyratex port IR patch from upstream to own code and see MGS don't able to register old OST in new MGS, with EINVAL.

collecting logs point to
mgs_handle_target_reg function and code

        /* Do not support unregistering right now. */
        if (opc != LDD_F_OPC_REG)
                GOTO(out_nolock, rc = -EINVAL);

in case 2.1 OST (or any pre IR target) don't set any flag from list

#define LDD_F_OPC_REG   0x10000000
#define LDD_F_OPC_UNREG 0x20000000
#define LDD_F_OPC_READY 0x40000000
#define LDD_F_OPC_MASK  0xf0000000

at own side and opc is zero. that broke target to be register.

PS. did you have interoperability testing for IR ?

Comments

[Alexey Lyashkov]

Fix looks simple, if target isn't IR capable, we must don't search may operations from submited info and assume operation is LDD_F_OPC_REG.

that code was don't need if IR author mark LDD_F_OPC_REG to zero, but now it's protocol change.

[Alexey Lyashkov]

diff --git a/lustre/mgs/mgs_handler.c b/lustre/mgs/mgs_handler.c
index 83fcdb6..f17f81a 100644
--- a/lustre/mgs/mgs_handler.c
+++ b/lustre/mgs/mgs_handler.c
@@ -494,7 +494,12 @@ static int mgs_handle_target_reg(struct ptlrpc_request *req)
 
         mti = req_capsule_client_get(&req->rq_pill, &RMF_MGS_TARGET_INFO);
 
+       if ((req->rq_export->exp_connect_data.ocd_connect_flags 
+               & OBD_CONNECT_IMP_RECOV) == 0)
+               opc = LDD_F_OPC_REG;
+       else
         opc = mti->mti_flags & LDD_F_OPC_MASK;
+
         if (opc == LDD_F_OPC_READY) {
                 CDEBUG(D_MGS, "fs: %s index: %d is ready to reconnect.\n",
                        mti->mti_fsname, mti->mti_stripe_index);

fixes bug for me.

[Alexey Lyashkov]

remote: New Changes:
remote: http://review.whamcloud.com/5574

Xyratex bug: MRP-880

[Jodi Levi (Inactive)]

James,
Could you please see this one to completion?

[James Nunez (Inactive)]

Sure. I've got it.

[Peter Jones]

Landed for 2.4