Resolvido.
meu erro
A opçãonbc-server "-r" é somente leitura. ..
remove "-r" e o mount -o loop opera corretamente
eu tento inserir memória USB e verificar se o dispositivo é "/ dev / sdb1"
root@ubuntu:~# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 64G 0 disk
├─sda1 8:1 0 63G 0 part /
├─sda2 8:2 0 1K 0 part
└─sda5 8:5 0 1022M 0 part [SWAP]
sdb 8:16 1 3.8G 0 disk
└─sdb1 8:17 1 3.8G 0 part /media/fd74eeb0-2bf8-49b0-872a- 4a283f124c10
sr0 11:0 1 1024M 0 rom
sr1 11:1 1 1024M 0 rom
e crie um dispositivo de rede
nbd-server -r 2000 /dev/sdb
** (process:2778): WARNING **: Specifying an export on the command line is deprecated.
** (process:2778): WARNING **: Please use a configuration file instead.
e lado do cliente (mesma máquina)
nbd-client 172.20.10.3 2000 /dev/nbd0
Negotiation: ..size = 3850MB
bs=1024, sz=4037017600 bytes
e montar o dispositivo nbd
mount -o loop /dev/nbd0p1 point/
mas monte da seguinte forma o problema ocorre
root@ubuntu# mount /dev/nbd0p1 point/
mount: block device /dev/nbd0p1 is write-protected, mounting read-only
quando tentei modificar arquivos em erros de dispositivo ocorridos
vi point/test.c
add lines
and :wq
point/test.c" E212: Can't open file for writing
porque ??
eu não entendo isso
root@ubuntu:~# dmesg | tail
[ 371.280809] loop: Write error at byte offset 3035136, length 4096.
[ 371.280810] Buffer I/O error on device loop0, logical block 741
[ 371.280812] lost page write due to I/O error on loop0
[ 371.280815] loop: Write error at byte offset 4096, length 4096.
[ 371.280816] Buffer I/O error on device loop0, logical block 1
[ 371.280818] lost page write due to I/O error on loop0
[ 389.039901] loop: Write error at byte offset 8396800, length 4096.
[ 389.039909] EXT4-fs warning (device loop0): ext4_end_bio:317: I/O error -1 writing to inode 12 (offset 0 size 0 starting block 2050)
[ 389.039913] Buffer I/O error on device loop0, logical block 2050
[ 391.266099] hrtimer: interrupt took 8643276 ns
Resolvido.
meu erro
A opçãonbc-server "-r" é somente leitura. ..
remove "-r" e o mount -o loop opera corretamente