File corruption turns file to read only cannot delete

[skeal]

I have 2 files in my root folder that are messed up and won't open. One is /opt and the other is /media without these files working I can't install anything. How do I format my root directory and rewrite? How do I remove these unremovable files? I was manually configuring dnscrypt to launch a second instance so I could have two dns servers. Help please! I am over my head I think.

Edit: will recovery mode work?
Edit: I have tried factory restore and uploading new firmware still these files cannot be opened.

 

[ColinTaylor]

/opt and /media are symbolic links to /tmp/opt and /tmp/media. By default the target directories don't exist for those two links. That is normal for the router.

 

[skeal]

/opt and /media are symbolic links to /tmp/opt and /tmp/media. By default the target directories don't exist for those two links. That is normal for the router.

I cannot see these files as folders they are now listed as an unrecognized file type. I cannot via command line in an ssh session find these files or use them in the way I had them before this happened. I use winscp and I can see the files but they are not represented as a folder or link.

 

[ColinTaylor]

Show us what you are seeing.

 

[skeal]

Show us what you are seeing.

View attachment 8833

Exactly the same as the screen shot above. They are read only files now. Can't install anything.

 

[ColinTaylor]

If you're seeing exactly that same as in my screenshot then there is no problem. That is normal. You can't modify any files/folders in the root directory because they exist in ROM and are therefore read-only. That is why there are symbolic links to /tmp which is modifiable because it resides in RAM.

 

[john9527]

All the files in root are mounted read-only (they are part of the firmware). You most likely corrupted the link target of /tmp/opt (which is another link to your entware install) or your entware install itself.

What's the output of

ll /tmp/opt (that's two small letter L)

 

[sfx2000]

If the files are still open, it's going to be hard to delete them...

SSH/Telnet into the router and do the following command, and see if the files show up in the response - lsof

 

[skeal]

If you're seeing exactly that same as in my screenshot then there is no problem. That is normal. You can't modify any files/folders in the root directory because they exist in ROM and are therefore read-only. That is why there are symbolic links to /tmp which is modifiable because it resides in RAM.

OK I'll get back to you if I have any trouble I'm updating right now to merlins 380.65_2. Then I'll try installing absolution and dnscrypt again. Thank you for your quick reply and help.

 

[skeal]

All the files in root are mounted read-only (they are part of the firmware). You most likely corrupted the link target of /tmp/opt (which is another link to your entware install) or your entware install itself.

What's the output of

ll /tmp/opt (that's two small letter L)

If the files are still open, it's going to be hard to delete them...

SSH/Telnet into the router and do the following command, and see if the files show up in the response - lsof

Results

ASUSWRT-Merlin RT-AC68U 380.65-2 Fri Mar 10 05:29:50 UTC 2017
Quincy@RT-AC68U-B790:/tmp/home/root# ll /tmp/opt
ls: /tmp/opt: No such file or directory
Quincy@RT-AC68U-B790:/tmp/home/root# lsof
-sh: lsof: not found
Quincy@RT-AC68U-B790:/tmp/home/root# - lsof
-sh: -: not found

 

[skeal]

All the files in root are mounted read-only (they are part of the firmware). You most likely corrupted the link target of /tmp/opt (which is another link to your entware install) or your entware install itself.

What's the output of

ll /tmp/opt (that's two small letter L)

Results

Quincy@RT-AC68U-B790:/tmp/home/root# ll /tmp/opt
ls: /tmp/opt: No such file or directory
Quincy@RT-AC68U-B790:/tmp/home/root#

 

[john9527]

Quincy@RT-AC68U-B790:/tmp/home/root# ll /tmp/opt
ls: /tmp/opt: No such file or directory

The answer....you deleted the link to your entware install.....

Here's what it should look like (pointing to your install location of course)

lrwxrwxrwx    1 admin    root            23 Dec 31  2010 /tmp/opt -> /tmp/mnt/extsys/entware/

You can try and recreate the proper link in /tmp, or since you may have also deleted part of entware, probably best to start from a clean slate, including a fresh entware install.

 

[skeal]

The answer....you deleted the link to your entware install.....

Here's what it should look like (pointing to your install location of course)

lrwxrwxrwx    1 admin    root            23 Dec 31  2010 /tmp/opt -> /tmp/mnt/extsys/entware/

You can try and recreate the proper link in /tmp, or since you may have also deleted part of entware, probably best to start from a clean slate, including a fresh entware install.

Installed entware that fixed /tmp.
Now I have that /media to take care of any ideas?

 

[john9527]

Now I have that /media to take care of any ideas?

Doesn't hurt anything......nothing to do (and nothing you can do).

 

[skeal]

Doesn't hurt anything......nothing to do (and nothing you can do).

Thank you sir!! You helped me lots!
I'm ok with nothing I can do.....lol.

 

[john9527]

Thank you sir!! You helped me lots!
I'm ok with nothing I can do.....lol.

LOL
Just to complete the thread. I imagine there is some addon package, somewhere, that looks for a media directory in root.....so the firmware provides one with a link to a writeable location. Just like it does for /opt to facilitate the installation of entware/optware.

 

[ColinTaylor]

Just FYI, it's part of the standard Linux filesystem. Even though /media is "official" in my experience most Linux distro's still use /mnt for a lot of removable devices.

 

[john9527]

Just FYI, it's part of the standard Linux filesystem. Even though /media is "official" in my experience most Linux distro's still use /mnt for a lot of removable devices.

I didn't know that....thanks for the info.

 

[sfx2000]

I didn't know that....thanks for the info.

Happens... I've been caught by that a couple of times...

/foo isn't a good place to be

/media is getting to be common place, even for devices that are mounted in /mnt - so this gets a bit odd...

And let's not mention the /usr merge

For those - the /usr merge, and reasons why - it's complicated... but there's a lot of history there that goes all the way back to Ancient Unix... and a lot of work to unwind that - because the *nix community tends to leave things alone...

 

[martinr]

... I'll try installing absolution ..

When I see this, just for a second, I think there's so much extra stuff you can load onto your poor router; why, they've even got software that offers forgiveness.