This is the conlog replica.
It appears to have started around 5:00 PM and repeated each hour after. I had to restart the database replication, it appears that the database has been crashing in response. It may not be a coincidence that the search for frequently changing channels also runs every hour, so I have disabled it.
cdsadmin@h1conlog3:/var/log$ grep error syslog
Feb 4 17:04:08 h1conlog3 kernel: [2335398.323116] res 51/40:0a:16:e8:88/00:00:00:00:00/0b Emask 0x9 (media error)
Feb 4 17:04:08 h1conlog3 kernel: [2335398.323407] ata3.00: error: { UNC }
Feb 4 17:04:08 h1conlog3 kernel: [2335398.344358] Add. Sense: Unrecovered read error - auto reallocate failed
Feb 4 17:04:08 h1conlog3 kernel: [2335398.344367] end_request: I/O error, dev sda, sector 193521686
Feb 4 17:04:11 h1conlog3 kernel: [2335401.397976] res 51/40:02:16:e8:88/00:00:00:00:00/0b Emask 0x9 (media error)
Feb 4 17:04:11 h1conlog3 kernel: [2335401.398264] ata3.00: error: { UNC }
Feb 4 17:04:11 h1conlog3 kernel: [2335401.420344] Add. Sense: Unrecovered read error - auto reallocate failed
Feb 4 17:04:11 h1conlog3 kernel: [2335401.420352] end_request: I/O error, dev sda, sector 193521686
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