[Nexus S Q&A, Help & Troubleshooting] Jacks0n:
Attempting to partition sd card with ext4 -a process I completed multiple times successfully on a Nexus One, the process appeared to complete but now the phone will not mount the sd card. I've tried a wipe/reset, to no avail. I can still access and partition the sd card through adb, but the phone cannot mount it to format/partition, restore from recovery, partition sd-card from within ClockWork Recovery, nothing. I've re-partitioned the sd card through adb, which indicated a successful completion, but the phone still refuses to mount the sd card. If this weren't a Nexus S with it's cursed internal sd-card I would simply swap out the sd card with another or format it externally like all the google topics I pull up on the subject suggest.

Is this fixable or has the fused sd-card scenario become a liability?

Common Error messages:

Can't mount /sdcard

Can't mount /sdcard/.android_secure

Phone: Nexus S (US, T-Mobile, manufactured Dec. '10)

Recovery Img: ClockworkMod Recovery 3.0.2.4

Rom: CM 7.0.3 (now wiped, cannot put back on since sd card won't mount)

fstab:

/dev/block/mtdblock4 /cache yaffs2 rw

/dev/block/platform/s3c-sdhci.0/by-name/userdata /data ext4 rw

/dev/block/platform/s3c-sdhci.0/by-name/system /system ext4 rw

/dev/block/platform/s3c-sdhci.0/by-name/media /sdcard vfat rw

Can mount everything except the last one, /sdcard.

I've tried all the recommended procedures garnered from the first 10 or so pages in google, xda, cyanogem forum, etc:

Restore from nandroid: Not possible, can't mount the SD,

Wipe/Reset: can't wipe /media as sd card won't mount,

partition sd card from within Clockwork: indicates success but does nothing,

format from within clockwork: unable to mount,

repartition using adb: works, parted can see them, I can move files to from, but the phone will not mount,

clearing fstab: no effect,

Fastboot works, but I don't have the proper images. ADB works, as do the installed utilities. Have not tried ODIN as again, I don't have the proper images. Should I attempt to compile my own images from source?

Update: SOLVED, Microsoft Windows. To whom it may concern: I was able to mount the /dev/block/platform/s3c-sdhci.0/by-name/media from two different laptops running OSX and Fedora/Ubuntu then successfully been able to partition them with fat32 as the ClockworkMod (and maybe Cyanogen?) expect with 0 progress. Then I pulled out an old Windows machine, installed the JDK/ADK's +tools and performed the same procedure and that time it worked. I'm uncertain as to what particular quality a 'genuine' Windows formatting provides, but either this phone or the particular software combination I'm running require it. I was able to mount & re-partition the /sdcard in Clockwork, then manually remove rebuild them and upgrade to ext4 using tune2fs as usual. In the interim for work and such, I had to find a surrogate (for the SIM) and could only find and old k750i (which still had a full charge and worked flawlessly all day, btw). Wow phones used to be small.

I think I was missing something about the way ClockworkMod handles fstab, because everytime I would modify it specifically to the specs I passed to parted while creating the partitions with mkpartfs, it would either ignore or overwrite them. So be careful messing with the sd-card, the S's aren't like the One's in the sense that if you screw it (the sd-card) up or it goes bad you can't just take it out and format it in another machine/phone, you have to appeal to ClockworkMod. ODIN $ucks by the way, I found fastboot to be much more effective.