preserve replicated ETag properly on target (#16129)

cmd/object-api-options.go

@@ -293,6 +293,7 @@ func putOpts(ctx context.Context, r *http.Request, bucket, object string, metada
 			Err:    fmt.Errorf("invalid/unknown checksum sent: %v", err),
 		}
 	}
+	etag := strings.TrimSpace(r.Header.Get(xhttp.MinIOSourceETag))
 
 	if crypto.S3KMS.IsRequested(r.Header) {
 		keyID, context, err := crypto.S3KMS.ParseHTTP(r.Header)
@@ -311,6 +312,7 @@ func putOpts(ctx context.Context, r *http.Request, bucket, object string, metada
 			VersionSuspended:     versionSuspended,
 			MTime:                mtime,
 			WantChecksum:         wantCRC,
+			PreserveETag:         etag,
 		}, nil
 	}
 	// default case of passing encryption headers and UserDefined metadata to backend
@@ -325,6 +327,7 @@ func putOpts(ctx context.Context, r *http.Request, bucket, object string, metada
 	opts.ReplicationSourceLegalholdTimestamp = lholdtimestmp
 	opts.ReplicationSourceRetentionTimestamp = retaintimestmp
 	opts.ReplicationSourceTaggingTimestamp = taggingtimestmp
+	opts.PreserveETag = etag
 	opts.WantChecksum = wantCRC
 
 	return opts, nil