I add ssh key, this error occur. I use a staic node in nodepool. this node is a ubuntu sys. I only config ssh key.
Task  **Export legacy syslog.txt** failed running on host **controller**
```
journalctl
  -t kernel
  -t sudo
  --no-pager
  --since="$(cat /opt/stack/log-start-timestamp.txt)" 
  > /home/zuul/logs/syslog.txt
 non-zero return code
 cat: /opt/stack/log-start-timestamp.txt: No such file or directory
 [0;1;31mFailed to parse timestamp: [0m
```