Help needed! Raid 5 failure on a Debian System

Hello!

I have a 4-disc Raid 5 server running Open Media Vault (Debian). The other day, it disappeared from OMV, which was reporting 3 drives failed. Panic Stations. However, using MDADM I can get info from 3 of the drives which suggests they are functioning ok (info below). The remaining 4th drive doesn't give anything back via mdadm --examine. Any ideas how I can rebuild the drive without destroying the data? According to what I have read, as the three apparently working drives all have the same events number (103), it is fairly likely the data is intact on them - but how to I rebuild?

Thanks my lovelies!

Jon

/dev/sdf:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x0
Array UUID : dc344271:82f55bd0:fcfd0e16:a2a60bc8
Name : TTVServer:TTV2 (local to host TTVServer)
Creation Time : Mon Jan 7 11:03:39 2013
Raid Level : raid5
Raid Devices : 4

Avail Dev Size : 5860531120 (2794.52 GiB 3000.59 GB)
Array Size : 17581590528 (8383.56 GiB 9001.77 GB)
Used Dev Size : 5860530176 (2794.52 GiB 3000.59 GB)
Data Offset : 2048 sectors
Super Offset : 8 sectors
State : active
Device UUID : c792c6b2:78fd4e78:e4f008ea:826e25e8

Update Time : Sat Apr  6 13:17:10 2013
   Checksum : 30386dbe - correct
     Events : 103

     Layout : left-symmetric
 Chunk Size : 512K

Device Role : Active device 0
Array State : AAAA ('A' == active, '.' == missing)

/dev/sdg:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x0
Array UUID : dc344271:82f55bd0:fcfd0e16:a2a60bc8
Name : TTVServer:TTV2 (local to host TTVServer)
Creation Time : Mon Jan 7 11:03:39 2013
Raid Level : raid5
Raid Devices : 4

Avail Dev Size : 5860531120 (2794.52 GiB 3000.59 GB)
Array Size : 17581590528 (8383.56 GiB 9001.77 GB)
Used Dev Size : 5860530176 (2794.52 GiB 3000.59 GB)
Data Offset : 2048 sectors
Super Offset : 8 sectors
State : active
Device UUID : c0426118:614cb315:15c9a0ee:2ad88e26

Update Time : Sat Apr  6 13:17:10 2013
   Checksum : 7638ae70 - correct
     Events : 103

     Layout : left-symmetric
 Chunk Size : 512K

Device Role : Active device 1
Array State : AAAA ('A' == active, '.' == missing)

/dev/sdi:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x0
Array UUID : dc344271:82f55bd0:fcfd0e16:a2a60bc8
Name : TTVServer:TTV2 (local to host TTVServer)
Creation Time : Mon Jan 7 11:03:39 2013
Raid Level : raid5
Raid Devices : 4

Avail Dev Size : 5860531120 (2794.52 GiB 3000.59 GB)
Array Size : 17581590528 (8383.56 GiB 9001.77 GB)
Used Dev Size : 5860530176 (2794.52 GiB 3000.59 GB)
Data Offset : 2048 sectors
Super Offset : 8 sectors
State : active
Device UUID : 8a96d5fe:594418b6:c63dafd0:c459e498

Update Time : Sat Apr  6 13:17:10 2013
   Checksum : 5175f080 - correct
     Events : 103

     Layout : left-symmetric
 Chunk Size : 512K

Device Role : Active device 2
Array State : AAAA ('A' == active, '.' == missing)

Ok after some more reading, I tried this:

and got this:

aaaghhh!!!

---------- Post updated at 10:17 PM ---------- Previous update was at 10:13 PM ----------

also...

---------- Post updated at 10:29 PM ---------- Previous update was at 10:17 PM ----------

also: