errors that cause proxy to move worker to error state

[Jeff Trawick]

It looks like this is just 500 and 503.

Why not 400, for example?

        if (access_status == OK)
            break;
        else if (access_status == HTTP_INTERNAL_SERVER_ERROR) {
            /* Unrecoverable server error.
             * We can not failover to another worker.
             * Mark the worker as unusable if member of load balancer
             */
            if (balancer) {
                worker->s->status |= PROXY_WORKER_IN_ERROR;
                worker->s->error_time = apr_time_now();
            }
            break;
        }
        else if (access_status == HTTP_SERVICE_UNAVAILABLE) {
            /* Recoverable server error.
             * We can failover to another worker
             * Mark the worker as unusable if member of load balancer
             */
            if (balancer) {
                worker->s->status |= PROXY_WORKER_IN_ERROR;
                worker->s->error_time = apr_time_now();
            }
        }
        else {
            /* Unrecoverable error.
             * Return the origin status code to the client.
             */
            break;
        }