Quando montei meu disco rígido externo pela primeira vez, ele afirma ser montado rw:
# mkdir /media/external-hdd
# mount /dev/sdb1 /media/external-hdd
# mount | grep sdb1
/dev/sdb1 on /media/external-hdd type ext3 (rw,relatime,errors=continue,user_xattr,acl,barrier=1,data=ordered)
No entanto, se eu tentar escrever nele, recebo um erro e agora aparece como somente leitura:
# touch /media/external-hdd/test
touch: cannot touch `/media/external-hdd/test': Read-only file system
# mount | grep sdb1
/dev/sdb1 on /media/external-hdd type ext3 (ro,relatime,errors=continue,user_xattr,acl,barrier=1,data=ordered)
Edição: Eu acho que tem algo a ver com o diário ext3, como eu recebo o seguinte ao executar dmesg:
[4964983.186798] EXT3-fs (sdb1): warning: mounting fs with errors, running e2fsck is recommended
[4964983.187960] EXT3-fs (sdb1): using internal journal
[4964983.187970] EXT3-fs (sdb1): recovery complete
[4964983.192469] EXT3-fs (sdb1): mounted filesystem with ordered data mode
[4964989.011023] end_request: I/O error, dev sdb, sector 976492584
[4964989.011040] Buffer I/O error on device sdb1, logical block 122061317
[4964989.011048] lost page write due to I/O error on sdb1
[4964989.011081] Aborting journal on device sdb1.
[4965081.221503] EXT3-fs (sdb1): error: ext3_journal_start_sb: Detected aborted journal
[4965081.221520] EXT3-fs (sdb1): error: remounting filesystem read-only