I have a nearly full external HDD mounted under /mnt. This HDD is around 1TB in size. My primary hard drive is around 200GB. Because of the relatively large difference in size of the two, linux sees my whole system as being past 95% full point which violates the reserved space requirement of 5%. Naturally, this causes me to not be able to log in because I'm not allowed to use that space. (I've reduced the reserved space requirement to 1% for the time being so I can log in.).My question: how can I fix this? I have only consumed 3% of my primary hard drive space meaning I have nearly 200GB of available space. It doesn't seem reasonable that I should be locked out due to insufficient space just because I have a nearly full external hard drive mounted. Is there a fix to this?[edit to provide more detail upon request]me@xxxx ~ $ mountsysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)udev on /dev type devtmpfs (rw,nosuid,relatime,size=5065004k,nr_inodes=1266251,mode=755)devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000)tmpfs on /run type tmpfs (rw,nosuid,noexec,relatime,size=1023832k,mode=755)/dev/sda1 on / type ext4 (rw,noatime,errors=remount-ro,data=ordered)securityfs on /sys/kernel/security type securityfs (rw,nosuid,nodev,noexec,relatime)tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev)tmpfs on /run/lock type tmpfs (rw,nosuid,nodev,noexec,relatime,size=5120k)tmpfs on /sys/fs/cgroup type tmpfs (rw,mode=755)cgroup on /sys/fs/cgroup/systemd type cgroup (rw,nosuid,nodev,noexec,relatime,xattr,release_agent=/lib/systemd/systemd-cgroups-agent,name=systemd)pstore on /sys/fs/pstore type pstore (rw,nosuid,nodev,noexec,relatime)cgroup on /sys/fs/cgroup/devices type cgroup (rw,nosuid,nodev,noexec,relatime,devices)cgroup on /sys/fs/cgroup/net_cls,net_prio type cgroup (rw,nosuid,nodev,noexec,relatime,net_cls,net_prio)cgroup on /sys/fs/cgroup/cpu,cpuacct type cgroup (rw,nosuid,nodev,noexec,relatime,cpu,cpuacct)cgroup on /sys/fs/cgroup/perf_event type cgroup (rw,nosuid,nodev,noexec,relatime,perf_event,release_agent=/run/cgmanager/agents/cgm-release-agent.perf_event)cgroup on /sys/fs/cgroup/cpuset type cgroup (rw,nosuid,nodev,noexec,relatime,cpuset,clone_children)cgroup on /sys/fs/cgroup/memory type cgroup (rw,nosuid,nodev,noexec,relatime,memory)cgroup on /sys/fs/cgroup/freezer type cgroup (rw,nosuid,nodev,noexec,relatime,freezer)cgroup on /sys/fs/cgroup/pids type cgroup (rw,nosuid,nodev,noexec,relatime,pids,release_agent=/run/cgmanager/agents/cgm-release-agent.pids)cgroup on /sys/fs/cgroup/blkio type cgroup (rw,nosuid,nodev,noexec,relatime,blkio)cgroup on /sys/fs/cgroup/hugetlb type cgroup (rw,nosuid,nodev,noexec,relatime,hugetlb,release_agent=/run/cgmanager/agents/cgm-release-agent.hugetlb)systemd-1 on /proc/sys/fs/binfmt_misc type autofs (rw,relatime,fd=37,pgrp=1,timeout=0,minproto=5,maxproto=5,direct)debugfs on /sys/kernel/debug type debugfs (rw,relatime)mqueue on /dev/mqueue type mqueue (rw,relatime)hugetlbfs on /dev/hugepages type hugetlbfs (rw,relatime)fusectl on /sys/fs/fuse/connections type fusectl (rw,relatime)/dev/sda6 on /home type ext4 (rw,noatime,data=ordered)/dev/sdb1 on /mnt/media_drive type ext3 (rw,noatime,data=ordered)binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,relatime)cgmfs on /run/cgmanager/fs type tmpfs (rw,relatime,size=100k,mode=755)tmpfs on /run/user/122 type tmpfs (rw,nosuid,nodev,relatime,size=1023832k,mode=700,uid=122,gid=131)tmpfs on /run/user/1000 type tmpfs (rw,nosuid,nodev,relatime,size=1023832k,mode=700,uid=1000,gid=1000)gvfsd-fuse on /run/user/1000/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,relatime,user_id=1000,group_id=1000)me@xxxx ~ $ dfFilesystem     1K-blocks      Used Available Use% Mounted onudev             5065004         0   5065004   0% /devtmpfs            1023832     35556    988276   4% /run/dev/sda1       19091584  11288172   7591732  60% /tmpfs            5119144    510692   4608452  10% /dev/shmtmpfs               5120         4      5116   1% /run/locktmpfs            5119144         0   5119144   0% /sys/fs/cgroup/dev/sda6      207550056   6631692 190352376   4% /home/dev/sdb1      961301000 830560452  81902548  92% /mnt/media_drivecgmfs                100         0       100   0% /run/cgmanager/fstmpfs            1023832         0   1023832   0% /run/user/122tmpfs            1023832        20   1023812   1% /run/user/1000For the df command which shows 60%, it was showing as 100% yesterday but I deleted a lot of stuff (emptied trash, etc.). It's important to note that it shouldn't be currently showing 60% either as the drive is closer to 3% full.I got the following error when I would try to log on. Your session only lasted less than 10 seconds. If you have not logged  out yourself, this could mean that there is some installation problem  or that you may be out of diskspace. Try logging in with one of the  failsafe sessions to see if you can fix this problem. [ ] View  details(~/.xsession-errors file)I dropped to shell and ran df and noticed my system (/dev/sda1) was 100% full. I deleted my trash and some large files in my downloads directory. I also ran tune2fs to set my reserved space requirement to 1% to allow myself some space to log in graphically. 
Linux Mint - External drive causing my file system to look full and giving me the no space left on device error
linux;linux mint;mount;disk usage;fstab