I have been exploring files in bash, and in /etc/ssl/certs, most of the filenames are light blue. There is a red filename though, and I can't figure out why it is red.

Most of the files in this directory are .pem files. The red one is also a .pem file. It happens to be something like China_Internet_Network_Information_Center...pem

According to this stack exchange question , light blue filenames mean linked files, while red file names mean "archived" files. What does that mean? Looking at the directory with ls -all, I still can't tell what makes the filename red. Can anyone explain why it is red?

  • 3
    sounds like ls is coloring the files based on certain criteria; it might be helpful to include the ls -al output. My suspicion is a broken symlink.
    – Jeff Schaller
    Commented Feb 17, 2017 at 18:23
  • 1
    also, the result of echo $LS_COLORS
    – Jeff Schaller
    Commented Feb 17, 2017 at 18:25
  • 3
    By the way, there is no such ls option as -all.  There is a -a (all) option and a -l (long) option.  When you say ls -all, you are specifying the -a option once and the -l option twice (which does no good). You might as well just say ls -al. (Or ls -la, or ls -a -l or ls -l -a, all of which are equivalent.) Commented Feb 17, 2017 at 20:49
  • 1
    My guess would be a broken link, as the file is in a directory with other links. ls -lah the file to confirm. Commented Feb 18, 2017 at 9:31
  • you can edit /etc/profile.d/colorls.sh and change auto to none at the bottom of the file where it does the alias of ls. I never liked any of that color highlighting. alias l='ls -FC' ftw!
    – ron
    Commented Feb 1, 2023 at 14:18

2 Answers 2


First you need to know the VT100 color code


I don't know what your text actually looks like, but "red text" is 31.

Then you want to look at the dircolors command, and find everything that has a 31 in it. In my case, that would be:


Then you can go here


which tells you

  • or is an "orphan", a symbolic link with no target
  • the rest are file globs that match assorted archive and compression schemes

.pem doesn't appear on my list, and .pem files aren't colored on my system, so I can't help you further than that. But I'd guess "orphan".

  • It turned out to be an orphan. Another question: How did you output dircolors line by line like that?
    – jabe
    Commented Feb 20, 2017 at 18:01
  • @jabe -- i did it by hand, looking for colons and replacing them with returns.
    – hymie
    Commented Feb 21, 2017 at 1:02
  • @jabe -- i can't edit my older comment, so dircolors | sed -e 's/:/\n/g'
    – hymie
    Commented Feb 21, 2017 at 16:31

Most Linux distros by default usually color-code files so you can immediately recognize what type they are. You are right that red means archive file and .pem is an archive file. An archive file is just a file composed of other files. Examples you might be more familiar with might include .zip, .rar, or .tar files.

If you want to know more about .pem files this post has a good explanation

  • 3
    Linux is the kernel, and has no concept of color codes for file names. You are talking about the default bash (or another shell) configuration included in the distribution.
    – phihag
    Commented Feb 17, 2017 at 22:29
  • 2
    @phihag: It's probably not whatever shell you're using, but (as mentioned above) specific to the ls command. You can use the option --color=never to turn colorization off (my choice), or the dircolors command to set it to whatever you prefer.
    – jamesqf
    Commented Feb 18, 2017 at 0:50
  • Archive? Only context I know of pem is with cryptographic keys. Is it even allowed to contain arbitrary data?
    – jpmc26
    Commented Feb 18, 2017 at 1:16
  • @jpmc26 it contains multiple certificates in one .pem so it is considered an archive file.
    – ProdIssue
    Commented Feb 18, 2017 at 13:29
  • The weird thing is, is that the vast majority of the .pem files there are light blue. I suspect it is a broken link.
    – jabe
    Commented Feb 18, 2017 at 18:53

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