Currently unreadable (pending) sectors.

[NasKar]

I just got an alert
CRITICAL
Device: /dev/da0 [SAT], 2 Currently unreadable (pending) sectors.

The manual recommends "Before physically removing the failed device, go to Storage ➞ Pools. Select the pool name then click  (Settings). Select Status and locate the failed disk."

after doing a zpool status

Code:

  pool: freenas-boot
 state: ONLINE
  scan: scrub repaired 0 in 0 days 00:00:07 with 0 errors on Wed Apr  8 03:45:07 2020
config:

    NAME        STATE     READ WRITE CKSUM
    freenas-boot  ONLINE       0     0     0
      ada0p2    ONLINE       0     0     0

errors: No known data errors

  pool: v1
 state: ONLINE
  scan: none requested
config:

    NAME                                            STATE     READ WRITE CKSUM
    v1                                              ONLINE       0     0     0
      raidz2-0                                      ONLINE       0     0     0
        gptid/c2d52d01-748b-11ea-8163-0cc47a086882  ONLINE       0     0     0
        gptid/c2f25715-748b-11ea-8163-0cc47a086882  ONLINE       0     0     0
        gptid/c39fbe63-748b-11ea-8163-0cc47a086882  ONLINE       0     0     0
        gptid/c347705c-748b-11ea-8163-0cc47a086882  ONLINE       0     0     0
        gptid/c30bbf15-748b-11ea-8163-0cc47a086882  ONLINE       0     0     0
        gptid/c36f4a92-748b-11ea-8163-0cc47a086882  ONLINE       0     0     0
        gptid/c3ccfbbe-748b-11ea-8163-0cc47a086882  ONLINE       0     0     0
        gptid/c2bcb47b-748b-11ea-8163-0cc47a086882  ONLINE       0     0     0
      raidz2-1                                      ONLINE       0     0     0
        gptid/4e950414-748c-11ea-8163-0cc47a086882  ONLINE       0     0     0
        gptid/4f379f6b-748c-11ea-8163-0cc47a086882  ONLINE       0     0     0
        gptid/50441330-748c-11ea-8163-0cc47a086882  ONLINE       0     0     0
        gptid/505f045f-748c-11ea-8163-0cc47a086882  ONLINE       0     0     0
        gptid/5069a4bf-748c-11ea-8163-0cc47a086882  ONLINE       0     0     0
        gptid/5097b5f1-748c-11ea-8163-0cc47a086882  ONLINE       0     0     0
        gptid/50a264a1-748c-11ea-8163-0cc47a086882  ONLINE       0     0     0
        gptid/50cf0062-748c-11ea-8163-0cc47a086882  ONLINE       0     0     0

errors: No known data errors

1) I'm puzzled by the fact that my pool status is not degraded? Do I need to replace the drive or just keep an eye on it. I have a spare that I've burned in already.
2) Why didn't the system email me about the alert? I can get an email when I send a system/email/send test email.
3) If I purchase a new spare could I turn off the FreeNAS and connect a sata cable to a free port on the motherboard and use it to burn in test the replacement drive?
4) Finally smartctl –a /dev/da0 returns You have provided 2 device names: Is that because I have 2 vdev's? What is the correct syntax?