Not syncing every 10 minutes! version 1.1.5

[leoliyuanduo]

I am running a full node and a harvester on two windows desktop. Both of them are also plotting at the same time. Currently, the full node GUI will show 'Not synced' every 10-20 minutes and it will back to sync in about five minutes. It happens so often. It occurs like a routine. I have been observing it. Half of time it is not farming while half of time it is farming. I have opened my port '8444' on router. My debug log show INFO level. The only errors I can see during not syncing period are listed as bellow.

2021-05-15T12:03:xx full_node full_node_server : ERROR Exception: <class 'concurrent.futures._base.CancelledError'>, closing connection {'host': '127.0.0.1', 'port': 8449}. Traceback (most recent call last):
File "chia\server\server.py", line 531, in api_call
File "asyncio\tasks.py", line 435, in wait_for
concurrent.futures._base.CancelledError

2021-05-15T12:07:xx full_node chia.full_node.full_node_store: INFO Don't have challenge hash , caching EOS
2021-05-15T12:07:32.392 full_node chia.full_node.full_node: INFO End of slot not added CC challenge
2021-05-15T12:07:32.392 full_node full_node_server : INFO <- request_transaction from peer
2021-05-15T12:07:32.392 full_node full_node_server : INFO -> respond_transaction to peer xxx.xxx.xx.44
2021-05-15T12:07:32.402 full_node full_node_server : INFO <- respond_end_of_sub_slot from peer xxx.xxx.xxx.xxx
2021-05-15T12:07:32.402 full_node chia.full_node.full_node_store: INFO Don't have challenge hash , caching EOS
2021-05-15T12:07:32.402 full_node chia.full_node.full_node: INFO End of slot not added CC challenge
2021-05-15T12:07:32.421 full_node full_node_server : INFO <- respond_end_of_sub_slot from peer xx.xx.x.xxx
2021-05-15T12:07:32.423 full_node chia.full_node.full_node_store: INFO Don't have challenge hash , caching EOS
2021-05-15T12:07:32.423 full_node chia.full_node.full_node: INFO End of slot not added CC challenge

[BrandtH22]

If you are still experiencing the issues it is recommended to upgrade to the latest version of chia. Please download it from here: https://www.chia.net/downloads/

Since this issue has been open for a number of years without additional comments, we will be closing this ticket but if we have closed this ticket in error do not hesitate to reach out to us again with any followup questions, comments, or if the issue persists after an update.

Please note that upgrading major versions of chia generally requires the config.yaml to be recreated using these steps:
1. Stop chia
2. Rename the config or move it to a different directory
3. In CLI run chia init
4. Copy any custom settings from the old config to the new (plot drive directories, pool info, trusted node info, etc) - be careful here as yaml is very picky about formatting including those leading spaces
5. Start Chia

The best place to reach our support team is on Discord (https://discord.gg/chia) or by reopening this ticket.