从一天到第二天，Ubuntu 14.04 停止识别任何 USB 媒体。插入 USB 棒或我的 Android 手机会发出熟悉的咔嗒声，但 nemo 或本机文件管理器中未列出任何设备。
然而，该设备被列在lsusb：
Bus 002 Device 004: ID 17ef:1003 Lenovo Integrated Smart Card Reader
HERE---->Bus 002 Device 007: ID 058f:6387 Alcor Micro Corp. Flash Drive
Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 004: ID 04f2:b221 Chicony Electronics Co., Ltd integrated camera
Bus 001 Device 003: ID 0a5c:217f Broadcom Corp. BCM2045B (BDC-2.1)
Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
它确实出现在sudo fdisk -l
Disk /dev/sda: 256.1 GB, 256060514304 bytes
255 heads, 63 sectors/track, 31130 cylinders, total 500118192 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x000e7ed2
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 2000895 999424 83 Linux
/dev/sda2 2002942 300003327 149000193 5 Extended
/dev/sda3 300003328 500117503 100057088 83 Linux
/dev/sda5 2002944 20000767 8998912 82 Linux swap / Solaris
/dev/sda6 20002816 90001407 34999296 83 Linux
/dev/sda7 90003456 260001791 84999168 83 Linux
/dev/sda8 260003840 280002559 9999360 83 Linux
/dev/sda9 280004608 300003327 9999360 83 Linux
Disk /dev/sdb: 8189 MB, 8189378560 bytes
224 heads, 63 sectors/track, 1133 cylinders, total 15994880 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000
Device Boot Start End Blocks Id System
HERE----> /dev/sdb1 32 15994879 7997424 c W95 FAT32 (LBA)
奇怪的是，这种情况同时发生在两台运行 Ubuntu 14.04 和 Gnome3 的 PC 上。这绝对不是 USB 介质的问题。我尝试了 2 个不同的 USB 棒以及我的 Android 手机！但是，将 USB 鼠标插入同一个 USB 插头却没有问题。
我真的很困惑！出了什么问题？谢谢！
PS:输出形式dmesg：
[ 827.926196] usb-storage 2-1.2:1.0: USB Mass Storage device detected
[ 827.926376] scsi13 : usb-storage 2-1.2:1.0
[ 828.927655] scsi 13:0:0:0: Direct-Access Generic Flash Disk 8.07 PQ: 0 ANSI: 4
[ 828.928340] sd 13:0:0:0: Attached scsi generic sg2 type 0
[ 828.929768] sd 13:0:0:0: [sdb] 15994880 512-byte logical blocks: (8.18 GB/7.62 GiB)
[ 828.930884] sd 13:0:0:0: [sdb] Write Protect is off
[ 828.930897] sd 13:0:0:0: [sdb] Mode Sense: 23 00 00 00
[ 828.932008] sd 13:0:0:0: [sdb] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
[ 828.939865] sdb: sdb1
[ 828.943416] sd 13:0:0:0: [sdb] Attached SCSI removable disk
编辑：
备注：
USB 记忆棒和我的手机也在 Ubuntu 磁盘程序（以前的磁盘实用程序？）中列出。
答案1
从操作系统的角度来看，USB 记忆棒和 Android 手机是两种截然不同的东西。手机使用 mtpfs 来连接操作系统，而 USB 记忆棒则用作普通存储介质。尝试手动安装它们。mount /dev/sdb1 /mnt && nemo /mnt
看看是否可行。完成后umount /mnt