Support the ability to replace the chainlink don, without replacing geth entirely

deployment/environment/crib/ccip_deployer.go

@@ -124,7 +124,7 @@ func DeployCCIPAndAddLanes(ctx context.Context, lggr logger.Logger, envConfig de
 
 	// ----- Part 2 -----
 	lggr.Infow("setting up ocr...")
-	*e, err = setupOCR(e, homeChainSel, feedChainSel)
+	*e, err = mustOCR(e, homeChainSel, feedChainSel, true)
 	if err != nil {
 		return DeployCCIPOutput{}, fmt.Errorf("failed to apply changesets for setting up OCR: %w", err)
 	}
@@ -204,17 +204,16 @@ func ConnectCCIPLanes(ctx context.Context, lggr logger.Logger, envConfig devenv.
 	}, nil
 }
 
-// ConfigureCCIPOCR is a group of changesets used from CRIB to configure OCR on a new setup
-// This sets up OCR on all chains in the envConfig by configuring the CCIP home chain
+// ConfigureCCIPOCR is a group of changesets used from CRIB to redeploy the chainlink don on an existing setup
 func ConfigureCCIPOCR(ctx context.Context, lggr logger.Logger, envConfig devenv.EnvironmentConfig, homeChainSel, feedChainSel uint64, ab deployment.AddressBook) (DeployCCIPOutput, error) {
 	e, _, err := devenv.NewEnvironment(func() context.Context { return ctx }, lggr, envConfig)
 	if err != nil {
 		return DeployCCIPOutput{}, fmt.Errorf("failed to initiate new environment: %w", err)
 	}
 	e.ExistingAddresses = ab
 
-	lggr.Infow("setting up ocr...")
-	*e, err = setupOCR(e, homeChainSel, feedChainSel)
+	lggr.Infow("resetting ocr...")
+	*e, err = mustOCR(e, homeChainSel, feedChainSel, false)
 	if err != nil {
 		return DeployCCIPOutput{}, fmt.Errorf("failed to apply changesets for setting up OCR: %w", err)
 	}
@@ -503,16 +502,18 @@ func setupLanes(e *deployment.Environment, state changeset.CCIPOnChainState) (de
 	)
 }
 
-func setupOCR(e *deployment.Environment, homeChainSel uint64, feedChainSel uint64) (deployment.Environment, error) {
+func mustOCR(e *deployment.Environment, homeChainSel uint64, feedChainSel uint64, newDons bool) (deployment.Environment, error) {
 	chainSelectors := e.AllChainSelectors()
 	var ocrConfigPerSelector = make(map[uint64]changeset.CCIPOCRParams)
 	for selector := range e.Chains {
 		ocrConfigPerSelector[selector] = changeset.DeriveCCIPOCRParams(changeset.WithDefaultCommitOffChainConfig(feedChainSel, nil),
 			changeset.WithDefaultExecuteOffChainConfig(nil),
 		)
 	}
-	return commonchangeset.Apply(nil, *e, nil,
-		commonchangeset.Configure(
+
+	var commitChangeset commonchangeset.ConfiguredChangeSet
+	if newDons {
+		commitChangeset = commonchangeset.Configure(
 			// Add the DONs and candidate commit OCR instances for the chain
 			deployment.CreateLegacyChangeSet(changeset.AddDonAndSetCandidateChangeset),
 			changeset.AddDonAndSetCandidateChangesetConfig{
@@ -525,7 +526,28 @@ func setupOCR(e *deployment.Environment, homeChainSel uint64, feedChainSel uint6
 					PluginType:                      types.PluginTypeCCIPCommit,
 				},
 			},
-		),
+		)
+	} else {
+		commitChangeset = commonchangeset.Configure(
+			// Update commit OCR instances for existing chains
+			deployment.CreateLegacyChangeSet(changeset.SetCandidateChangeset),
+			changeset.SetCandidateChangesetConfig{
+				SetCandidateConfigBase: changeset.SetCandidateConfigBase{
+					HomeChainSelector: homeChainSel,
+					FeedChainSelector: feedChainSel,
+				},
+				PluginInfo: []changeset.SetCandidatePluginInfo{
+					{
+						OCRConfigPerRemoteChainSelector: ocrConfigPerSelector,
+						PluginType:                      types.PluginTypeCCIPCommit,
+					},
+				},
+			},
+		)
+	}
+
+	return commonchangeset.Apply(nil, *e, nil,
+		commitChangeset,
 		commonchangeset.Configure(
 			// Add the exec OCR instances for the new chains
 			deployment.CreateLegacyChangeSet(changeset.SetCandidateChangeset),

integration-tests/testconfig/ccip/ccip.toml

@@ -243,13 +243,12 @@ ephemeral_addresses_number = 0
 
 [Load.CCIP.Load]
 # MessageTypeWeights corresponds with [data only, token only, message with token]
-#MessageTypeWeights = [100,0,0]
 MessageTypeWeights = [100,0,0]
 # each destination chain will receive 1 incoming request per RequestFrequency for the duration of LoadDuration
 RequestFrequency = "5s"
-LoadDuration = "1h"
+LoadDuration = "10m"
 # destination chain selectors to send messages to
-NumDestinationChains = 30
+NumDestinationChains = 8
 # Directory where we receive environment configuration from crib
 CribEnvDirectory = "../../../../crib/deployments/ccip-v2/.tmp"
-TimeoutDuration = "1h"
+TimeoutDuration = "20m"