Had a cable issue earlier today showing 2 drives running into issues and was using syslog to check everything was working. Down the rabbit hole I went and discovered my sda is now cranky and spitting out those same errors as listed above.
Apr 2 14:24:56 FS kernel: sd 0:0:0:0: [sda] tag#0 UNKNOWN(0x2003) Result: hostbyte=0x00 driverbyte=DRIVER_OK cmd_age=0s
Apr 2 14:24:56 FS kernel: sd 0:0:0:0: [sda] tag#0 Sense Key : 0x3 [current]
Apr 2 14:24:56 FS kernel: sd 0:0:0:0: [sda] tag#0 ASC=0x11 ASCQ=0x0
Apr 2 14:24:56 FS kernel: sd 0:0:0:0: [sda] tag#0 CDB: opcode=0x28 28 00 00 e6 e6 41 00 00 07 00
Apr 2 14:24:56 FS kernel: critical medium error, dev sda, sector 15132225 op 0x0:(READ) flags 0x0 phys_seg 7 prio class 2
Apr 2 14:24:56 FS kernel: Buffer I/O error on dev sda1, logical block 15130177, async page read
Apr 2 14:24:56 FS kernel: Buffer I/O error on dev sda1, logical block 15130178, async page read
Apr 2 14:24:56 FS kernel: Buffer I/O error on dev sda1, logical block 15130179, async page read
Apr 2 14:24:56 FS kernel: Buffer I/O error on dev sda1, logical block 15130180, async page read
Apr 2 14:24:56 FS kernel: Buffer I/O error on dev sda1, logical block 15130181, async page read
Apr 2 14:24:56 FS kernel: Buffer I/O error on dev sda1, logical block 15130182, async page read
Apr 2 14:24:56 FS kernel: Buffer I/O error on dev sda1, logical block 15130183, async page read
Apr 2 14:24:56 FS kernel: sd 0:0:0:0: [sda] tag#0 UNKNOWN(0x2003) Result: hostbyte=0x00 driverbyte=DRIVER_OK cmd_age=0s
Apr 2 14:24:56 FS kernel: sd 0:0:0:0: [sda] tag#0 Sense Key : 0x3 [current]
Apr 2 14:24:56 FS kernel: sd 0:0:0:0: [sda] tag#0 ASC=0x11 ASCQ=0x0
Apr 2 14:24:56 FS kernel: sd 0:0:0:0: [sda] tag#0 CDB: opcode=0x28 28 00 00 e6 e6 40 00 00 01 00
Which lead to what thumbdrive I was using, which is a Verbatim Store-N-Go 8 GB, it's the size of your thumbnail and disappears in to a USB port.
Best part (or worst?), it's been kicking since Dec 2015! Servers has been powered 24/7 since that time.
Thank you for the recommendations for a new thumbdrive and what needs to be done, just had to share the Verbatim company!