diff --git a/Makefile b/Makefile
index 851a5bda..ce38398e 100644
--- a/Makefile
+++ b/Makefile
@@ -427,11 +427,9 @@ sample_app_agent_proxy: undeploy_sample_app_agent_proxy ## Deploy sample app wit
 			echo "'SAMPLE_APP_NAMESPACE' must be specified."; \
 			exit 1; \
 		fi ;\
-		SECRET_HASH=`echo -n ${DEPLOY_NAMESPACE}/cryostat-sample/${SAMPLE_APP_NAMESPACE} | sha256sum`; \
+		SECRET_HASH=`echo -n ${DEPLOY_NAMESPACE}/cryostat-sample/${SAMPLE_APP_NAMESPACE} | sha256sum | cut -d' ' -f 1`; \
 	fi; \
-	$(CLUSTER_CLIENT) patch -f config/samples/sample-app-agent-tls-proxy.yaml --local=true --type=merge \
-	-p "{\"spec\":{\"template\":{\"spec\":{\"\$setElementOrder/volumes\":[{\"name\":\"agent-tls\"}],\"volumes\":[{\"\$retainKeys\":[\"name\",\"secret\"],\"name\":\"agent-tls\",\"secret\":{\"secretName\":\"cryostat-agent-$${SECRET_HASH}\"}}]}}}}" \
-	-o yaml | oc apply -f -
+	sed "s/REPLACEHASH/$${SECRET_HASH}/" < config/samples/sample-app-agent-tls-proxy.yaml | oc apply -f -
 
 .PHONY: undeploy_sample_app_agent
 undeploy_sample_app_agent: ## Undeploy sample app with Cryostat Agent.
diff --git a/config/samples/sample-app-agent-tls-proxy.yaml b/config/samples/sample-app-agent-tls-proxy.yaml
index 835ca91d..0efd3329 100644
--- a/config/samples/sample-app-agent-tls-proxy.yaml
+++ b/config/samples/sample-app-agent-tls-proxy.yaml
@@ -71,7 +71,7 @@ spec:
       volumes:
       - name: agent-tls
         secret:
-          secretName: cryostat-agent-abcd1234
+          secretName: cryostat-agent-REPLACEHASH
           defaultMode: 420
 ---
 apiVersion: v1