[LU-16823] add LNet and OBD connect flags for IPv6 peers

• Type: Improvement
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.16.0
• Labels: IPv6
• Severity: 3
• Assignee: James A Simmons
• Reporter: Andreas Dilger

Description

When nodes are connecting to peers the sender should set a bit in the connection that it supports IPv6 (large) NIDs. This would inform LNet discovery whether it is safe to reply with large NIDs during connection or ping replies.

At the Lustre level new clients should set an OBD_CONNECT2_LARGE_NID=0x100000000ULL flag in obd_connect_data so that the MGS knows whether it can safely reply with large NIDs in mgs_nidtbl_entry. That avoids the need to backport a patch (ala LU-13306) to allow old clients to mount a server with both IPv4 and IPv6 NIDs configured.

Issue Links

• is related to: LU-10391 LNET: Support IPv6
• is related to: LU-13306 allow clients to accept mgs_nidtbl_entry with IPv6 NIDs