diff --git a/changes/907.fix.md b/changes/907.fix.md
new file mode 100644
index 00000000000..7d43ce13e2f
--- /dev/null
+++ b/changes/907.fix.md
@@ -0,0 +1 @@
+Fix occasional random mismatch of cluster hostnames and actual container hostnames in cluster sessions under the host networking mode
diff --git a/src/ai/backend/manager/registry.py b/src/ai/backend/manager/registry.py
index 78bd6f38a24..2d03bf0c7b0 100644
--- a/src/ai/backend/manager/registry.py
+++ b/src/ai/backend/manager/registry.py
@@ -1304,7 +1304,7 @@ async def start_session(
                             agent_addr = item.agent_alloc_ctx.agent_addr.replace(
                                 "tcp://", ""
                             ).split(":", maxsplit=1)[0]
-                            cluster_ssh_port_mapping[f"{cluster_role}{index+1}"] = (
+                            cluster_ssh_port_mapping[item.kernel.cluster_hostname] = (
                                 agent_addr,
                                 port,
                             )