我正在使用多个 Compute Engine 实例，有时它们似乎会随机丢失网络访问权限。没有任何变化，在这种情况下，某个实例运行了大约 80 天，没有任何错误。
在 /var/log/syslog 中出现以下错误：
Jun 2 17:15:11 alpha google_guest_agent[451]: ERROR main.go:178 Error watching metadata: Get "http://169.254.169.254/computeMetadata/v1//?recursive=true&alt=j>
Jun 2 17:17:07 alpha vnstatd[457]: Warning: Writing cached data to database took 107.0 seconds.
Jun 2 17:17:50 alpha dhclient[355]: DHCPREQUEST for XXX on ens4 to 169.254.169.254 port 67
Jun 2 17:18:32 alpha dhclient[355]: DHCPACK of XXX from 169.254.169.254
Jun 2 17:20:37 alpha systemd[1]: Starting GCE Workload Certificate refresh...
Jun 2 17:22:32 alpha vnstatd[457]: Warning: Writing cached data to database took 119.8 seconds.
Jun 2 17:23:18 alpha OSConfigAgent[1177944]: 2023-06-02T17:21:31.4637Z OSConfigAgent Error main.go:231: Get "http://169.254.169.254/computeMetadata/v1/?recurs>
Jun 2 17:28:27 alpha vnstatd[457]: Warning: Writing cached data to database took 166.0 seconds.
Jun 2 17:32:25 alpha CRON[2851637]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Jun 2 17:39:26 alpha OSConfigAgent[1177944]: 2023-06-02T17:38:23.9547Z OSConfigAgent Error main.go:231: Get "http://169.254.169.254/computeMetadata/v1/?recurs>
Jun 2 17:40:28 alpha vnstatd[457]: Warning: Writing cached data to database took 561.0 seconds.
Jun 2 17:40:59 alpha vnstatd[457]: Warning: Writing cached data to database took 50.0 seconds.
Jun 2 17:41:39 alpha dhclient[355]: bound to XXX -- renewal in 73 seconds.
Jun 2 17:43:02 alpha dhclient[355]: DHCPREQUEST for XXX on ens4 to 169.254.169.254 port 67
Jun 2 17:43:43 alpha dhclient[355]: DHCPACK of XXX from 169.254.169.254
Jun 2 17:45:04 alpha vnstatd[457]: Warning: Writing cached data to database took 237.0 seconds.
Jun 2 17:53:23 alpha vnstatd[457]: Warning: Writing cached data to database took 462.3 seconds.
Jun 2 17:54:49 alpha vnstatd[457]: Warning: Writing cached data to database took 63.3 seconds.
Jun 2 17:58:09 alpha OSConfigAgent[1177944]: 2023-06-02T17:57:05.2089Z OSConfigAgent Error main.go:231: Get "http://169.254.169.254/computeMetadata/v1/?recurs>
Jun 2 18:03:45 alpha vnstatd[457]: Warning: Writing cached data to database took 469.3 seconds.
Jun 2 18:04:50 alpha dhclient[355]: bound to XXX -- renewal in 413 seconds.
Jun 2 18:07:40 alpha vnstatd[457]: Warning: Writing cached data to database took 47.5 seconds.
Jun 2 18:11:10 alpha OSConfigAgent[1177944]: 2023-06-02T18:09:28.2124Z OSConfigAgent Warning: Error waiting for task (attempt 1 of 10): rpc error: code = Unav>
Jun 2 18:11:57 alpha dhclient[355]: DHCPREQUEST for XXX on ens4 to 169.254.169.254 port 67
同时，磁盘写入速度始终处于最大值。大约 2 小时后，我可以通过 SSH 再次连接，一切又恢复正常。我还可以毫无问题地访问本地元数据服务器 (169.254.169.254)。
所有实例都运行 Debian 11。您认为这是 vnstat 造成的吗？