I need to write to a.txt. The file is owned by root with a read-write access. But still I cannot write over it with a sudo. Why?
% ls -l
total 8
-rw-r--r-- 1 root staff 6 Mar 24 00:30 a.txt
% sudo echo "hi" >> a.txt
zsh: permission denied: a.txt
The redirection happens before the commands are run, i.e. using the original user.
Work-around:
sudo sh -c 'echo "hi" >> a.txt'
Related
I want to fetch list of files from a server using SFTP one by one only if their size is less than 1 GB.
I am running the following command :
$sftp -oIdentityFile=/home/user/.ssh/id_rsa -oPort=22 user#hostname >list.txt <<EOF
cd upload/Example
ls -l iurygify*.zip
EOF
This results in:
$cat list.txt
sftp> cd upload/Example
sftp> ls -l iurygify*.zip
-rwxrwx--- 0 300096661 300026669 0 Mar 11 16:38 iurygify1.zip
-rwxrwx--- 0 300096661 300026669 0 Mar 11 16:38 iurygify2.zip
I could then use awk to calculate get the size and filename which I can save into logs for reference and then download only those files which meet the 1 GB criteria.
Is there any simpler approach to accomplish getting this file list and size? I want to avoid the junk entires of the prompt and commands in the list.txt and do not want to do this via expect command.
We are using SSH key authentication
You could place your sftp commands in a batch file and filter the output - no need for expect.
echo 'ls -l' > t
sftp -b t -oIdentityFile=/home/user/.ssh/id_rsa -oPort=22 user#hostname | grep -v 'sftp>' >list.txt
Or take it a step further and filter out the "right size" in the same step:
sftp -b t -oIdentityFile=/home/user/.ssh/id_rsa -oPort=22 user#hostname | awk '$1!~/sftp>/&&$5<1000000000' >list.txt
Maybe using lftp instead of sftp ?
$ lftp sftp://xxx > list.txt <<EOF
> open
> ls -l
> EOF
$ cat list.txt
drwxr-xr-x 10 ludo users 4096 May 24 2019 .
drwxr-xr-x 8 root root 4096 Dec 20 2018 ..
-rw------- 1 ludo users 36653 Mar 31 19:28 .bash_history
-rw-r--r-- 1 ludo users 220 Mar 21 2014 .bash_logout
-rw-r--r-- 1 ludo users 362 Aug 16 2018 .bash_profile
...
What does this command do in a Linux terminal?
chmod -r /home/daria/photos/
I got this question because there was no error
chmod is a utility that is used to change the permissions of a file or directory. You can use ls -l /path/to/file command to observe the changes of chmod.
❯ echo "XYZ" > /tmp/abc # Create a new file named abc
❯ ls -l /tmp/abc # List the permissions of /tmp/abc
-rw-r--r-- 1 abdulkarim wheel 4B Apr 3 13:17 /tmp/abc
❯ cat /tmp/abc # Display the contents of the file
XYZ
❯ chmod -r /tmp/abc # remove read permissions for User, Group and Others
❯ ls -l /tmp/abc # Notice the read perms are gone
--w------- 1 abdulkarim wheel 4B Apr 3 13:17 /tmp/abc
❯ cat /tmp/abc # We can no longer cat the file!
cat: /tmp/abc: Permission denied
So, the command chmod -r /path/to/file will revoke the read permissions for everyone. Similarly chmod +r will grant read permission to everyone.
The man page for chmod does not explain this, making it difficult for some users but once you know this, you cannot un-know this :)
I have a php script that will collection data and write log into a file, the directory belongs to an user called 'ingestion' and a group called 'ingestion'. I was using the command
sudo -u ingestion php [script] &>> /var/log/FOLDER/adapter.log
The owner and group of FOLDER is ingestion. However, the created adapter.log still belongs to root user and root group, how is this possible?
Your file is created by the bash running as root, not by the process that you run via sudo as ingestion.
That's because the >> foo is part of the command line, not of the process started by sudo.
Here:
#foo.sh
echo foo: `id -u`
Then:
tmp root# sudo -u peter bash foo.sh > foo
tmp root# ls -l foo
-rw------- 1 root staff 9 Mar 2 18:52 foo
tmp root# cat foo
foo: 501
You can see that the file is created as root but the foo.sh script is run as uid 501.
You can fix this by running e.g.:
tmp root# sudo -u peter bash -c "bash foo.sh > foo"
tmp root# ls -l foo
-rw------- 1 peter staff 9 Mar 2 18:54 foo
tmp root# cat foo
foo: 501
In your case, of course, replace "..." with your php command.
I am running a script but there is an unusual warning:
This is what happened in my console
#whoami
root
#ls -l test.sh
-rwxr-xr-x. 1 root root 1894 Feb 2 01:58 test.sh*
#./test.sh
-bash: ./test.sh: Permission denied
Edit:
my script:
#!/bin/bash
while read pass port user ip file; do
echo "startt------------------------------------" $ip
ping $ip -c 4
if [ $? -eq 0 ]; then
echo $ip ok...
else
echo $ip failed...
fi
echo "finish------------------------------------" $ip
done <<____HERE
pass 22 root 1.1.1.1 test.txt
____HERE
any idea?
thank you
I am running the script in /tmp directory
as you see the result of ls is:
-rwxr-xr-x. 1 root root 1894 Feb 2 01:58 test.sh*
there is . after permissions which indicates that an SELinux security context applies to that file. so I copied test.sh in a directory else...
the problem was solved
ls -l /
drwxrwxrwt. 8 root root 1024 Feb 2 07:44 tmp/
I was in a directory where it might be a bad idea for executables to reside
These may work as well:
setenforce 0 | reboot
OR
echo 0 > /selinux/enforce | reboot
OR:
putting SELINUX=disabled in /etc/selinux/config and reboot (making sure to comment out anything in that file enabling selinux)
SELINUX status: sestatus
I back up my files using rsync. Right after a sync, I ran it expecting to see nothing, but instead it looked like it was skipping directories. I've (obviously) changed names, but I believe I've still captured all the information I could. What's happening here?
$ ls -l /source/backup/myfiles
drwxr-xr-x 2 me me 4096 2010-10-03 14:00 foo
drwxr-xr-x 2 me me 4096 2011-08-03 23:49 bar
drwxr-xr-x 2 me me 4096 2011-08-18 18:58 baz
$ ls -l /destination/backup/myfiles
drwxr-xr-x 2 me me 4096 2010-10-03 14:00 foo
drwxr-xr-x 2 me me 4096 2011-08-03 23:49 bar
drwxr-xr-x 2 me me 4096 2011-08-18 18:58 baz
$ file /source/backup/myfiles/foo
/source/backup/myfiles/foo/: directory
Then I sync (expecting no changes):
$ rsync -rtvp /source/backup /destination
sending incremental file list
backup/myfiles
skipping non-regular file "backup/myfiles/foo"
skipping non-regular file "backup/myfiles/bar"
And here's the weird part:
$ echo 'hi' > /source/backup/myfiles/foo/test
$ rsync -rtvp /source/backup /destination
sending incremental file list
backup/myfiles
backup/myfiles/foo
backup/myfiles/foo/test
skipping non-regular file "backup/myfiles/foo"
skipping non-regular file "backup/myfiles/bar"
So it worked:
$ ls -l /source/backup/myfiles/foo
-rw-r--r-- 1 me me 3126091 2010-06-15 22:22 IMGP1856.JPG
-rw-r--r-- 1 me me 3473038 2010-06-15 22:30 P1010615.JPG
-rw-r--r-- 1 me me 3 2011-08-24 13:53 test
$ ls -l /destination/backup/myfiles/foo
-rw-r--r-- 1 me me 3126091 2010-06-15 22:22 IMGP1856.JPG
-rw-r--r-- 1 me me 3473038 2010-06-15 22:30 P1010615.JPG
-rw-r--r-- 1 me me 3 2011-08-24 13:53 test
but still:
$ rsync -rtvp /source/backup /destination
sending incremental file list
backup/myfiles
skipping non-regular file "backup/myfiles/foo"
skipping non-regular file "backup/myfiles/bar"
Other notes:
My actual directories "foo" and "bar" do have spaces, but no other strange characters. Other directories have spaces and have no problem. I 'stat'-ed and saw no differences between the directories that don't rsync and the ones that do.
If you need more information, just ask.
Are you absolutely sure those individual files are not symbolic links?
Rsync has a few useful flags such as -l which will "copy symlinks as symlinks". Adding -l to your command:
rsync -rtvpl /source/backup /destination
I believe symlinks are skipped by default because they can be a security risk. Check the man page or --help for more info on this:
rsync --help | grep link
To verify these are symbolic links or pro-actively to find symbolic links you can use file or find:
$ file /path/to/file
/path/to/file: symbolic link to `/path/file`
$ find /path -type l
/path/to/file
Are you absolutely sure that it's not a symbolic link directory?
try a:
file /source/backup/myfiles/foo
to make sure it's a directory
Also, it could very well be a loopback mount
try
mount
and make sure that /source/backup/myfiles/foo is not listed.
You should try the below command, most probably it will work for you:
rsync -ravz /source/backup /destination
You can try the following, it will work
rsync -rtvp /source/backup /destination
I personally always use this syntax in my script and works a treat to backup the entire system (skipping sys/* & proc/* nfs4/*)
sudo rsync --delete --stats --exclude-from $EXCLUDE -rlptgoDv / $TARGET/ | tee -a $LOG
Here is my script run by root's cron daily:
#!/bin/bash
#
NFS="/nfs4"
HOSTNAME=`hostname`
TIMESTAMP=`date "+%Y%m%d_%H%M%S"`
EXCLUDE="/home/gcclinux/Backups/root-rsync.excludes"
TARGET="${NFS}/${HOSTNAME}/SYS"
LOGDIR="${NFS}/${HOSTNAME}/SYS-LOG"
CMD=`/usr/bin/stat -f -L -c %T ${NFS}`
## CHECK IF NFS IS MOUNTED...
if [[ ! $CMD == "nfs" ]];then
echo "NFS NOT MOUNTED"
exit 1
fi
## CHECK IF LOG DIRECTORY EXIST
if [ ! -d "$LOGDIR" ]; then
/bin/mkdir -p $LOGDIR
fi
## CREATE LOG HEADER
LOG=$LOGDIR/"rsync_result."$TIMESTAMP".txt"
echo "-------------------------------------------------------" | tee -a $LOG
echo `date` | tee -a $LOG
echo "" | tee -a $LOG
## START RUNNING BACKUP
/usr/bin/rsync --delete --stats --exclude-from $EXCLUDE -rlptgoDv / $TARGET/ | tee -a $LOG
In some cases just copy file to another location (like home) then try again