[SOLVED] /etc/hosts file is read-only for root in ubuntu Server. But rw- is for root

Iyyappan · 03-13-2012, 10:27 AM

In my Ubuntu server 10 64bit, /etc/hosts file is read only. Rights of /etc/hosts are
-rw-r--r-- 1 root root 392 2012-03-09 09:55 hosts. But i am unable to edit the file. I do not have gui installed in it. /etc/resolv.conf is editable, but /etc/hosts file alone is not editable. This machine is in OPSource Cloud.

I have logged in as root user only. Kindly help

business_kid · 03-13-2012, 12:24 PM

Try this (as root)

Quote:

cat > /etc/hosts <<EOF

It will return
>
and you can type in lines and press return (you get another '>') and build up your new /etc/hosts. For the last line just type

>EOF

and it might write it.

The other basic check to run is
cd /etc
touch blah

you should get /etc/blah length zero bytes. That's the acid test of whether you have write permissions.

Iyyappan · 03-14-2012, 04:32 AM

I did as u said the output is as follows
O/P
> EOF
-bash: /etc/hosts: Permission denied

* i created another file werty in /etc
-rw-r--r-- 1 root root 0 2012-03-14 05:28 werty
i am able to edit the file werty. I am not able to edit /etc/host file alone.....

Any other ideas....

deep27ak · 03-14-2012, 06:02 AM

copy the contents of /etc/hosts file into a new file with same permission 644

Code:

#cp /etc/hosts /etc/hosts.bak <--take backup

#vi /etc/hosts1 <--create a new file
paste the lines from hosts file

#mv /etc/hosts1 /etc/hosts

Reuti · 03-14-2012, 06:59 AM

What does:

Code:

$ lsattr /etc/hosts

show?

Iyyappan · 03-14-2012, 08:31 AM

@Deepak
mv: cannot move `/etc/hosts1' to `/etc/hosts': Operation not permitted

@Reuti
lsattr /etc/hosts
O/P ==----i------------e- /etc/hosts

Interestingly lsattr /etchosts1 is
O/P -----------------e- /etc/hosts1

Reuti · 03-14-2012, 08:36 AM

Aha, then we have to change the immutable bit (see man chattr):

Code:

$ chattr -i /etc/hosts

Then it should be possible to work on it again.

Iyyappan · 03-14-2012, 08:44 AM

Done it worked great.....thanks. How did the attributes got changed. This was a new machine created in cloud. Is there any scenario under which this change occurs? But i have not done any change to system related files

Reuti · 03-14-2012, 08:51 AM

Was it installed by the provider or by you? I would assume that it was set up during installation to avoid that a bad setup could make the access to the machine impossible.

The only thing I wonder about now: the “e” showing up in your output. I don’t have it anywhere, and it’s also not explained in chattr man page. Is it explained in your version of the man page?

Iyyappan · 03-14-2012, 08:59 AM

Machine was created from an image hosted in Op source Cloud. It was created and hosted as an image by third party. May be he has changed the attributes after installation and then took an image of it and hosted in Cloud

Man Page:

The 'e' attribute indicates that the file is using extents for mapping the blocks on disk. It may not be removed using chattr(1).

The 'e' was not removed when i gave chattr command. 'e' is found in Ubuntu Server 10 alone. But not in CentOS

Reuti · 03-14-2012, 09:02 AM

Thx for posting the relevant information.

GoldenPaul27 · 10-01-2013, 01:45 AM

Code:

chattr -i /etc/hosts

This code gave me this error:

Code:

chattr: Permission denied while setting flags on /etc/hosts