RFC Errata
RFC 5661, "Network File System (NFS) Version 4 Minor Version 1 Protocol", January 2010
Note: This RFC has been obsoleted by RFC 8881
Note: This RFC has been updated by RFC 8178, RFC 8434
Source of RFC: nfsv4 (wit)
Errata ID: 5982
Status: Rejected
Type: Technical
Publication Format(s) : TEXT
Reported By: David Noveck
Date Reported: 2020-02-13
Rejected by: Magnus Westerlund
Date Rejected: 2020-09-03
Section 2.10.6.1.3.1 says:
If a requester sent a Sequence operation with a slot ID and sequence ID that are in the reply cache but the replier detected that the retried request is not the same as the original request, including a retry that has different operations or different arguments in the operations from the original and a retry that uses a different principal in the RPC request's credential field that translates to a different user, then this is a false retry. When the replier detects a false retry, it is permitted (but not always obligated) to return NFS4ERR_FALSE_RETRY in response to the Sequence operation when it detects a false retry.
It should say:
If a requester sent a Sequence operation with a slot ID and sequence ID that are in the reply cache but the replier detected that the retried request is not the same as the original request, including a retry that was issued with a different XID or has different operations or different arguments in the operations from the original and a retry that uses a different principal in the RPC request's credential field that translates to a different user, then this is a false retry. When the replier detects a false retry, it is permitted (but not always obligated) to return NFS4ERR_FALSE_RETRY in response to the Sequence operation when it detects a false retry
Notes:
The existing text can be read as requiring checksumming of all requests to foreclose the possibility of not noticing a false retry, which can result in data corruption. This can be a
significant performance consideraation in the processing of WRITE requests and could undercut the benefits of directly placing data to be written which is one of the impotant goals of RPC-over-RDMA.
--VERIFIER NOTES--
No consensus in the WG if this is just a correction. Thus rejecting the issue and may be brought for WG consenus discussion in the context of document update.