在Ubuntu中，你可以使用以下几种方法来查看已挂载的设备：
df命令df命令可以显示文件系统的磁盘空间使用情况，包括已挂载的设备。
df -h
-h选项表示以人类可读的格式显示（例如，MB、GB）。输出示例：
Filesystem Size Used Avail Use% Mounted on
udev 3.9G 0 3.9G 0% /dev
tmpfs 798M 1.7M 796M 1% /run
/dev/sda1 234G 20G 209G 9% /
tmpfs 3.9G 12M 3.9G 1% /dev/shm
tmpfs 5.0M 4.0K 5.0M 1% /run/lock
tmpfs 3.9G 0 3.9G 0% /sys/fs/cgroup
/dev/loop0 55M 55M 0 100% /snap/core18/1888
/dev/loop1 30M 30M 0 100% /snap/snapd/8169
/dev/loop2 30M 30M 0 100% /snap/snapd/8240
/dev/loop3 30M 30M 0 100% /snap/snapd/8312
/dev/loop4 30M 30M 0 100% /snap/snapd/8430
/dev/loop5 30M 30M 0 100% /snap/snapd/8506
/dev/loop6 30M 30M 0 100% /snap/snapd/8582
/dev/loop7 30M 30M 0 100% /snap/snapd/8649
/dev/loop8 30M 30M 0 100% /snap/snapd/8715
/dev/loop9 30M 30M 0 100% /snap/snapd/8782
/dev/loop10 30M 30M 0 100% /snap/snapd/8849
/dev/loop11 30M 30M 0 100% /snap/snapd/8915
/dev/loop12 30M 30M 0 100% /snap/snapd/8982
/dev/loop13 30M 30M 0 100% /snap/snapd/9049
/dev/loop14 30M 30M 0 100% /snap/snapd/9115
/dev/loop15 30M 30M 0 100% /snap/snapd/9182
/dev/loop16 30M 30M 0 100% /snap/snapd/9249
/dev/loop17 30M 30M 0 100% /snap/snapd/9315
/dev/loop18 30M 30M 0 100% /snap/snapd/9382
/dev/loop19 30M 30M 0 100% /snap/snapd/9449
/dev/loop20 30M 30M 0 100% /snap/snapd/9515
/dev/loop21 30M 30M 0 100% /snap/snapd/9582
/dev/loop22 30M 30M 0 100% /snap/snapd/9649
/dev/loop23 30M 30M 0 100% /snap/snapd/9715
/dev/loop24 30M 30M 0 100% /snap/snapd/9782
/dev/loop25 30M 30M 0 100% /snap/snapd/9849
/dev/loop26 30M 30M 0 100% /snap/snapd/9915
/dev/loop27 30M 30M 0 100% /snap/snapd/9982
/dev/loop28 30M 30M 0 100% /snap/snapd/10049
/dev/loop29 30M 30M 0 100% /snap/snapd/10115
/dev/loop30 30M 30M 0 100% /snap/snapd/10182
/dev/loop31 30M 30M 0 100% /snap/snapd/10249
/dev/loop32 30M 30M 0 100% /snap/snapd/10315
/dev/loop33 30M 30M 0 100% /snap/snapd/10382
/dev/loop34 30M 30M 0 100% /snap/snapd/10449
/dev/loop35 30M 30M 0 100% /snap/snapd/10515
/dev/loop36 30M 30M 0 100% /snap/snapd/10582
/dev/loop37 30M 30M 0 100% /snap/snapd/10649
/dev/loop38 30M 30M 0 100% /snap/snapd/10715
/dev/loop39 30M 30M 0 100% /snap/snapd/10782
/dev/loop40 30M 30M 0 100% /snap/snapd/10849
/dev/loop41 30M 30M 0 100% /snap/snapd/10915
/dev/loop42 30M 30M 0 100% /snap/snapd/10982
/dev/loop43 30M 30M 0 100% /snap/snapd/11049
/dev/loop44 30M 30M 0 100% /snap/snapd/11115
/dev/loop45 30M 30M 0 100% /snap/snapd/11182
/dev/loop46 30M 30M 0 100% /snap/snapd/11249
/dev/loop47 30M 30M 0 100% /snap/snapd/11315
/dev/loop48 30M 30M 0 100% /snap/snapd/11382
/dev/loop49 30M 30M 0 100% /snap/snapd/11449
/dev/loop50 30M 30M 0 100% /snap/snapd/11515
/dev/loop51 30M 30M 0 100% /snap/snapd/11582
/dev/loop52 30M 30M 0 100% /snap/snapd/11649
/dev/loop53 30M 30M 0 100% /snap/snapd/11715
/dev/loop54 30M 30M 0 100% /snap/snapd/11782
/dev/loop55 30M 30M 0 100% /snap/snapd/11849
/dev/loop56 30M 30M 0 100% /snap/snapd/11915
/dev/loop57 30M 30M 0 100% /snap/snapd/11982
/dev/loop58 30M 30M 0 100% /snap/snapd/12049
/dev/loop59 30M 30M 0 100% /snap/snapd/12115
/dev/loop60 30M 30M 0 100% /snap/snapd/12182
/dev/loop61 30M 30M 0 100% /snap/snapd/12249
/dev/loop62 30M 30M 0 100% /snap/snapd/12315
/dev/loop63 30M 30M 0 100% /snap/snapd/12382
/dev/loop64 30M 30M 0 100% /snap/snapd/12449
/dev/loop65 30M 30M 0 100% /snap/snapd/12515
/dev/loop66 30M 30M 0 100% /snap/snapd/12582
/dev/loop67 30M 30M 0 100% /snap/snapd/12649
/dev/loop68 30M 30M 0 100% /snap/snapd/12715
/dev/loop69 30M 30M 0 100% /snap/snapd/12782
/dev/loop70 30M 30M 0 100% /snap/snapd/12849
/dev/loop71 30M 30M 0 100% /snap/snapd/12915
/dev/loop72 30M 30M 0 100% /snap/snapd/12982
/dev/loop73 30M 30M 0 100% /snap/snapd/13049
/dev/loop74 30M 30M 0 100% /snap/snapd/13115
/dev/loop75 30M 30M 0 100% /snap/snapd/13182
/dev/loop76 30M 30M 0 100% /snap/snapd/13249
/dev/loop77 30M 30M 0 100% /snap/snapd/13315
/dev/loop78 30M 30M 0 100% /snap/snapd/13382
/dev/loop79 30M 30M 0 100% /snap/snapd/13449
/dev/loop80 30M 30M 0 100% /snap/snapd/13515
/dev/loop81 30M 30M 0 100% /snap/snapd/13582
/dev/loop82 30M 30M 0 100% /snap/snapd/13649
/dev/loop83 30M 30M 0 100% /snap/snapd/13715
/dev/loop84 30M 30M 0 100% /snap/snapd/13782
/dev/loop85 30M 30M 0 100% /snap/snapd/13849
/dev/loop86 30M 30M 0 100% /snap/snapd/13915
/dev/loop87 30M 30M 0 100% /snap/snapd/13982
/dev/loop88 30M 30M 0 100%
mount命令mount命令可以显示当前挂载的所有文件系统。
mount
输出示例：
/dev/sda1 on / type ext4 (rw,relatime,data=ordered)
udev on /dev type devtmpfs (rw,nosuid,noexec,relatime,size=3932124k,nr_inodes=983031,mode=755)
tmpfs on /run type tmpfs (rw,nosuid,noexec,relatime,size=798684k,mode=755)
/dev/loop0 on /snap/core18/1888 type squashfs (ro,relatime)
/dev/loop1 on /snap/snapd/8169 type squashfs (ro,relatime)
/dev/loop2 on /snap/snapd/8240 type squashfs (ro,relatime)
/dev/loop3 on /snap/snapd/8312 type squashfs (ro,relatime)
/dev/loop4 on /snap/snapd/8430 type squashfs (ro,relatime)
/dev/loop5 on /snap/snapd/8506 type squashfs (ro,relatime)
/dev/loop6 on /snap/snapd/8582 type squashfs (ro,relatime)
/dev/loop7 on /snap/snapd/8649 type squashfs (ro,relatime)
/dev/loop8 on /snap/snapd/8715 type squashfs (ro,relatime)
/dev/loop9 on /snap/snapd/8782 type squashfs (ro,relatime)
/dev/loop10 on /snap/snapd/8849 type squashfs (ro,relatime)
/dev/loop11 on /snap/snapd/8915 type squashfs (ro,relatime)
/dev/loop12 on /snap/snapd/8982 type squashfs (ro,relatime)
/dev/loop13 on /snap/snapd/9049 type squashfs (ro,relatime)
/dev/loop14 on /snap/snapd/9115 type squashfs (ro,relatime)
/dev/loop15 on /snap/snapd/9182 type squashfs (ro,relatime)
/dev/loop16 on /snap/snapd/9249 type squashfs (ro,relatime)
/dev/loop17 on /snap/snapd/9315 type squashfs (ro,relatime)
/dev/loop18 on /snap/snapd/9382 type squashfs (ro,relatime)
/dev/loop19 on /snap/snapd/9449 type squashfs (ro,relatime)
/dev/loop20 on /snap/snapd/9515 type squashfs (ro,relatime)
/dev/loop21 on /snap/snapd/9582 type squashfs (ro,relatime)
/dev/loop22 on /snap/snapd/9649 type squashfs (ro,relatime)
/dev/loop23 on /snap/snapd/9715 type squashfs (ro,relatime)
/dev/loop24 on /snap/snapd/9782 type squashfs (ro,relatime)
/dev/loop25 on /snap/snapd/9849 type squashfs (ro,relatime)
/dev/loop26 on /snap/snapd/9915 type squashfs (ro,relatime)
/dev/loop27 on /snap/snapd/9982 type squashfs (ro,relatime)
/dev/loop28 on /snap/snapd/10049 type squashfs (ro,relatime)
/dev/loop29 on /snap/snapd/10115 type squashfs (ro,relatime)
/dev/loop30 on /snap/snapd/10182 type squashfs (ro,relatime)
/dev/loop31 on /snap/snapd/10249 type squashfs (ro,relatime)
/dev/loop32 on /snap/snapd/10315 type squashfs (ro,relatime)
/dev/loop33 on /snap/snapd/10382 type squashfs (ro,relatime)
/dev/loop34 on /snap/snapd/10449 type squashfs (ro,relatime)
/dev/loop35 on /snap/snapd/10515 type squashfs (ro,relat