SERVER-19606 Upgrade / downgrade of election protocol version

1 files changed, 77 insertions, 0 deletions

diff --git a/jstests/replsets/protocol_version_upgrade_downgrade.js b/jstests/replsets/protocol_version_upgrade_downgrade.js
new file mode 100644
index 00000000000..214addff7e0
--- /dev/null
+++ b/jstests/replsets/protocol_version_upgrade_downgrade.js
@@ -0,0 +1,77 @@
+load("jstests/replsets/rslib.js");
+
+(function() {
+
+"use strict";
+var name = "protocol_version_upgrade_downgrade";
+var rst = new ReplSetTest({name: name, nodes: 3});
+
+rst.startSet();
+// Initiate the replset in protocol version 0.
+var conf = rst.getReplSetConfig();
+conf.settings = conf.settings || { };
+conf.settings.protocolVersion = 0;
+rst.initiate(conf);
+rst.awaitSecondaryNodes();
+
+var primary = rst.getMaster();
+var primaryColl = primary.getDB("test").coll;
+
+// Set verbosity for replication on all nodes.
+var verbosity = {
+    "setParameter" : 1,
+    "logComponentVerbosity" : {
+        "replication" : { "verbosity" : 3 },
+    }
+}
+primary.adminCommand(verbosity);
+rst.getSecondaries().forEach(function (node) {node.adminCommand(verbosity)});
+
+// Do a write, this will set up sync sources on secondaries.
+print("do a write");
+assert.writeOK(primaryColl.bar.insert({x: 1}, {writeConcern: {w: 3}}));
+// Check optime format in protocol version 0, which is a Timestamp.
+var res = primary.adminCommand({replSetGetStatus: 1});
+assert.commandWorked(res);
+assert.eq(res.members[0].optime.term, null);
+
+//
+// Upgrade protocol version
+//
+res = primary.adminCommand({replSetGetConfig: 1});
+assert.commandWorked(res);
+conf = res.config;
+assert.eq(conf.settings.protocolVersion, 0);
+// Change protocol version
+conf.settings.protocolVersion = 1;
+conf.version++;
+reconfig(rst, conf);
+// This write may block until all nodes finish upgrade, because replSetUpdatePosition may be
+// rejected by the primary for mismatched config version before secondaries get reconfig.
+// This will make secondaries blacklist the primary for 0.5 seconds.
+assert.writeOK(primaryColl.bar.insert({x: 2}, {writeConcern: {w: 3}}));
+
+// Check optime format in protocol version 1, which is an object including the term.
+res = primary.adminCommand({replSetGetStatus: 1});
+assert.commandWorked(res);
+assert.eq(res.members[0].optime.term, NumberLong(0));
+
+//
+// Downgrade protocol version
+//
+res = primary.adminCommand({replSetGetConfig: 1});
+assert.commandWorked(res);
+conf = res.config;
+assert.eq(conf.settings.protocolVersion, 1);
+// Change protocol version
+conf.settings.protocolVersion = 0;
+conf.version++;
+reconfig(rst, conf);
+assert.writeOK(primaryColl.bar.insert({x: 3}, {writeConcern: {w: 3}}));
+
+// Check optime format in protocol version 0, which is a Timestamp.
+res = primary.adminCommand({replSetGetStatus: 1});
+assert.commandWorked(res);
+assert.eq(res.members[0].optime.term, null);
+
+})();