# Files changed · PR \#23647 · pingdotgg/t3code

[View on GitCafe](https://git.cafe/pingdotgg/t3code/pull/23647/diffs)

Repository: [pingdotgg/t3code](https://git.cafe/pingdotgg/t3code)

Visibility: public

[fix\(web\): SSH environments on an older reused remote server explain the version mismatch instead of reconnecting forever](https://git.cafe/pingdotgg/t3code/pull/23647.md)

Version: 12

Head commit: 31019fac0f9d55584cfae7e66c6b13ab938ca451

Base commit: f054d1b8018721bd997d99cbb918a7b17bf098a4

Comparison base: f054d1b8018721bd997d99cbb918a7b17bf098a4

Showing up to 20 entries from this revision. If the pull request changes, reopen the first page before continuing.

## apps/desktop/src/ipc/methods/sshEnvironment.ts

Status: modified; +1; −0

```diff
@@ -83,6 +83,7 @@
   readonly cause: DesktopSshEnvironmentRequestCause;
   readonly sshHttpStatus: number | null;
 }> {
+  // The web client matches "[ssh_http:500]" to explain version-skewed SSH pairing.
   override get message() {
     const prefix = this.sshHttpStatus === null ? "" : `[ssh_http:${this.sshHttpStatus}] `;
     return `${prefix}SSH remote API request failed during ${this.operation}.`;
```

## apps/web/src/connection/platform.test.ts

Status: modified; +36; −0

```diff
@@ -28,6 +28,7 @@
   provisionDesktopSshEnvironment,
   secondaryRegistrationsToRetainAfterTopologyRead,
 } from "./platform.ts";
+import { APP_VERSION } from "../branding.ts";
 
 const TARGET: DesktopSshEnvironmentTarget = {
   alias: "devbox",
@@ -223,7 +224,42 @@
       expect(exchange).toHaveBeenCalledExactlyOnceWith(SSH_BOOTSTRAP.httpBaseUrl, "pairing-token");
     }),
   );
+
+  const failPairing = (serverVersion: string, message: string) => {
+    const bridge = makeBridge([]);
+    const fetchDescriptor = bridge.fetchSshEnvironmentDescriptor;
+    vi.spyOn(bridge, "fetchSshEnvironmentDescriptor").mockImplementation(async (url) => ({
+      ...(await fetchDescriptor(url)),
+      serverVersion,
+    }));
+    vi.spyOn(bridge, "bootstrapSshBearerSession").mockRejectedValue(new Error(message));
+    return provisionDesktopSshEnvironment(bridge, TARGET).pipe(Effect.flip);
+  };
+  const PAIRING_500 =
+    "[ssh_http:500] SSH remote API request failed during bootstrap-bearer-session.";
+
+  it.effect("blocks with both versions when a server on another build rejects pairing", () =>
+    Effect.gen(function* () {
+      const error = yield* failPairing("0.0.46-nightly.20261004.2652", PAIRING_500);
 
+      expect(error).toBeInstanceOf(ConnectionBlockedError);
+      expect(error.detail).toContain("0.0.46-nightly.20261004.2652");
+      expect(error.detail).toContain(APP_VERSION);
+    }),
+  );
+
+  it.effect("keeps retrying pairing failures that are not a version mismatch", () =>
+    Effect.gen(function* () {
+      expect(yield* failPairing(APP_VERSION, PAIRING_500)).toBeInstanceOf(ConnectionTransientError);
+      expect(
+        yield* failPairing(
+          "0.0.46-nightly.20261004.2652",
+          "SSH remote API request failed during bootstrap-bearer-session.",
+        ),
+      ).toBeInstanceOf(ConnectionTransientError);
+    }),
+  );
+
   it.effect("reconnects with the saved token while it holds every standard scope", () =>
     Effect.gen(function* () {
       const calls: string[] = [];
```

## apps/web/src/connection/platform.ts

Status: modified; +16; −1

```diff
@@ -238,7 +238,22 @@
   }
   const access = yield* Effect.tryPromise({
     try: () => bridge.bootstrapSshBearerSession(bootstrap.httpBaseUrl, pairingToken),
+    catch: (cause) => {
+      const error = sshPreparationError(cause);
+      // A reused remote server on another build can fail to decode the grant
+      // the desktop's runner just minted, and answers 500 on every retry.
+      if (
+        error._tag === "ConnectionBlockedError" ||
+        descriptor.serverVersion === APP_VERSION ||
+        !error.detail.includes("[ssh_http:500]")
+      ) {
-    catch: sshPreparationError,
+        return error;
+      }
+      return new ConnectionBlockedError({
+        reason: "configuration",
+        detail: `${descriptor.label} runs T3 Code ${descriptor.serverVersion}, but this desktop is ${APP_VERSION}, and that server could not accept its pairing. Restart the T3 server on ${descriptor.label} so it runs ${APP_VERSION}, then retry.`,
+      });
+    },
   });
   return {
     environmentId: descriptor.environmentId,
```