This is how my logs look like:

chat-synapse-1  | 2023-01-30 09:03:24,465 - synapse.handlers.device - 1273 - WARNING - _maybe_retry_device_resync-3501- Failed to handle device list update for @REDACTED.example.com: 403: Forbidden
chat-synapse-1  | 2023-01-30 09:03:24,679 - synapse.http.matrixfederationclient - 709 - WARNING - _maybe_retry_device_resync-3501- {GET-O-60894641} [synapse.solarinet.org] Request failed: GET matrix://REDACTED/_matrix/federation/v1/user/devices/REDACTED: HttpResponseException('302: Found')
chat-synapse-1  | 2023-01-30 09:03:24,679 - synapse.handlers.device - 1273 - WARNING - _maybe_retry_device_resync-3501- Failed to handle device list update for @REDACTED.example.com: 302: Found
chat-synapse-1  | 2023-01-30 09:03:24,690 - synapse.http.matrixfederationclient - 709 - WARNING - _maybe_retry_device_resync-3501- {GET-O-60894644} [matrix.litness.de] Request failed: GET matrix://REDACTED/_matrix/federation/v1/user/devices/REDACTED: HttpResponseException('404: Not Found')
chat-synapse-1  | 2023-01-30 09:03:24,691 - synapse.handlers.device - 1273 - WARNING - _maybe_retry_device_resync-3501- Failed to handle device list update for @REDACTED.example.com: 404: Not Found
chat-synapse-1  | 2023-01-30 09:03:24,705 - synapse.http.matrixfederationclient - 709 - WARNING - _maybe_retry_device_resync-3501- {GET-O-60894691} [matrix.appsforce.org] Request failed: GET matrix://REDACTED/_matrix/federation/v1/user/devices/REDACTED: HttpResponseException('403: Forbidden')
chat-synapse-1  | 2023-01-30 09:03:24,706 - synapse.handlers.device - 1273 - WARNING - _maybe_retry_device_resync-3501- Failed to handle device list update for @REDACTED.example.com: 403: Forbidden
chat-synapse-1  | 2023-01-30 09:03:24,921 - synapse.http.matrixfederationclient - 709 - WARNING - _maybe_retry_device_resync-3501- {GET-O-60894704} [synapse.solarinet.org] Request failed: GET matrix://REDACTED/_matrix/federation/v1/user/devices/REDACTED: HttpResponseException('302: Found')
chat-synapse-1  | 2023-01-30 09:03:24,921 - synapse.handlers.device - 1273 - WARNING - _maybe_retry_device_resync-3501- Failed to handle device list update for @REDACTED.example.com: 302: Found
chat-synapse-1  | 2023-01-30 09:03:24,935 - synapse.http.matrixfederationclient - 709 - WARNING - _maybe_retry_device_resync-3501- {GET-O-60894705} [matrix.appsforce.org] Request failed: GET matrix://REDACTED/_matrix/federation/v1/user/devices/REDACTED: HttpResponseException('403: Forbidden')
chat-synapse-1  | 2023-01-30 09:03:24,936 - synapse.handlers.device - 1273 - WARNING - _maybe_retry_device_resync-3501- Failed to handle device list update for @REDACTED.example.com: 403: Forbidden
chat-synapse-1  | 2023-01-30 09:03:25,040 - synapse.http.matrixfederationclient - 709 - WARNING - _maybe_retry_device_resync-3501- {GET-O-60894731} [akuj.in] Request failed: GET matrix://REDACTED/_matrix/federation/v1/user/devices/REDACTED: HttpResponseException('403: Forbidden')
chat-synapse-1  | 2023-01-30 09:03:25,040 - synapse.handlers.device - 1273 - WARNING - _maybe_retry_device_resync-3501- Failed to handle device list update for @REDACTED.example.com: 403: Forbidden
chat-synapse-1  | 2023-01-30 09:03:25,044 - synapse.http.matrixfederationclient - 709 - WARNING - _maybe_retry_device_resync-3501- {GET-O-60894739} [ring0.de] Request failed: GET matrix://REDACTED/_matrix/federation/v1/user/devices/REDACTED: HttpResponseException('404: Not Found')
chat-synapse-1  | 2023-01-30 09:03:25,045 - synapse.handlers.device - 1273 - WARNING - _maybe_retry_device_resync-3501- Failed to handle device list update for @REDACTED.example.com: 404: Not Found
chat-synapse-1  | 2023-01-30 09:03:25,209 - synapse.http.matrixfederationclient - 709 - WARNING - _maybe_retry_device_resync-3501- {GET-O-60894832} [synapse.glester.com] Request failed: GET matrix://REDACTED/_matrix/federation/v1/user/devices/REDACTED: HttpResponseException('403: Forbidden')

How can I reduce these specific WARNING messages without reducing the log level? They’re so spammy that I a) can’t see anything else going on without extensively grepping and b) it’s filling up my disk to the point that 80GB of logs on the docker partition made my server go boom.