In an Amazon Linux instance, after deployment using ElasticBeanstalk, all the files are owned by root user:
drwxr-xr-x 25 root root 4096 jan 01 00:00 var
But the current user is ec2-user so I don't have permissions to create/modify inside /var folder anything. What is the best approach to make it work? chown and modify owner to ec2-user? add user to a user group if exists which I don't know... any other idea?
I don't have permissions to create/modify inside /var folder anything.
you can use following ways to achieve this.
Try sudo [your command]
sudo chown user directory
sudo bash //this will make your root directly
But beware for 2 and 3 way, it can break your system if you do something wrong.There is a famous saying hope you know what you will do
On a Ubuntu machine I've setup a SVN repository, served with Apache.
All the SVN repository folders and subfolders (located under /var/svn/repos/) belongs to www-data user and group:
drwxr-xr-x 7 www-data www-data 4096 gen 21 10:38 software_repository
www-data is the Apache user.
Next I've a cron job that makes a nightly svnadmin dump of the repository, using my home user, let's say john_doe (joining the www-data group too). svnadmin dump command (and more...) are contained in a sh file called by the crond.
During cron job or launching it manually using user john_doe I get:
svnadmin: E160052: Revprop caching for '/var/svn/repos/sw/software_repository/db' disabled because SHM infrastructure for revprop caching failed to initialize.
svnadmin: E000013: Can't open file '/var/svn/repos/sw/software_repository/db/rev-prop-atomics.mutex': Permission denied
Because of Permission denied error, I've run the same sh script prepending sudo command, and everything works fine.
So, we have 2 possibilities:
Understand where the SVN error come from.
Change permissions in a correct way for the john_doe user, used by cron.
For point #1 I've done some Google search but I've found nothing...
For point #2, I think the correct way is not to set all permissions (recursively) of the group www-data to all SVN folders and subfolders. What it could be done is to share permissions on SVN folders between www-data user and john_doe. Or give to the www-data group the same permissions (recursively) of the www-data user. Or something else, but for both solutions I've no idea of the correct command or configuration setting.
Solved running command:
chmod -R g=u software_repository
This fix is for solution 2. By the way I've no clue where the SVN errors come from...
I have moved my website from Godaddy to a VPS server. I'm new to Linux so I followed some tutorials online but still confused about some problems.
I use SSH to log on my server as user adam. In order to run the PHP properly, I have to set 755 permission to /var/www and change the owner of this folder to www-data. But that means I don't have permission to write files in this folder even if add user adam to the group www-data. And I cannot upload webpages onto this folder using FTP which is very annoying. (Currently I have to type su to switch to root and then modify these files with nano)
I know setting 777 is a solution but it may cause some safety concerns so I'm looking for a better solution.
drwxr-xr-x 8 www-data www-data 4096 Jul 24 21:36 www
Every number of permisson is composed as follows
4: read
2: write
1: execute
So if you add them you get the permission. By example 7 means all the permisons and 6 means read and write.
The first number of 755 is for the owner, the second for the group's users and the third for other users.
Then 755 means rwxr-xr-x it is the owner can read wirte and execute, but the group member can't write.
If you want to solve this you can change the privileges to 775 then it will be change to rwxrwr-x
Or you can add www-data as a secondary group to adam and set a setgroupid www-data fro /var/www
Please let me explain what I mean by the question:
This is the context: I'm a user on a webserver, where I have phpicalendar installed; then, I choose a directory, say /webroot/mylogin/phpicalendar/mycals to host my .ics calendar text files.
EDIT: Previously, instead of '/webroot', I had used '/root' - but I really didn't mean the Linux '/root' directory - I'm just wanted to use it as a stand in for the real location on the webserver (so it serves just as a common point of reference). Otherwise, what I mean by common point of reference, is simply /webroot = /media/some/path ..
Then, I can enter this directory in the phpicalendar's config.inc.php:
$configs = array(
'calendar_path' => '/webroot/mylogin/phpicalendar/mycals;
...
Then, phpicalendar will run through this directory, grab the .ics files there (say, mycal.ics and mycal2.ics) and render them - so far, so good.
The thing is, I would now like to add a second calendar directory, located at the same webserver, but where I have read-only permissions, say /webroot/protected/cals. I know that I have read permissions, because I can do in the shell, say
$ less /webroot/protected/cals/maincal.ics
and I can read the contents fine.. So now:
If I enter /webroot/protected/cals as a 'calendar_path', phpicalendar can read and render the files there (say, 'maincal.ics', 'maincal2.ics') without a problem
However, phpicalendar can have only one 'calendar_path', so I can either use the protected calendars, or my customized calendars - but not both
So, I thought, I could symlink the protected calendars in my customized directory - and get the best of both worlds :)
So, here is a shell snippet of what I would do
$ cd /webroot/mylogin/phpicalendar/mycals
$ ls -la
drwxrwxrwx 2 myself myself 4096 2011-03-03 12:50 .
-rw-r--r-- 1 myself myself 1234 2011-01-20 07:32 mycal.ics
-rw-r--r-- 1 myself myself 1234 2011-01-20 07:32 mycal2.ics
...
$ ln /webroot/protected/cals/maincal.ics . # try a hard link first
ln: creating hard link `./maincal.ics' => `/webroot/protected/cals/maincal.ics': Invalid cross-device link'
$ ln -s /webroot/protected/cals/maincal.ics . # symlink - works
$ ln -s ../../../protected/cals/maincal.ics relmaincal.ics # symlink via relative
$ ln -s mycal.ics testcal.ics # try a symlink to a local file
$ ls -la # check contents of dir now
drwxrwxrwx 2 myself myself 4096 .
-rw-r--r-- 1 myself myself 1234 mycal.ics
-rw-r--r-- 1 myself myself 1234 mycal2.ics
lrwxrwxrwx 1 myself myself 21 testcal.ics -> mycal.ics
lrwxrwxrwx 1 myself myself 56 maincal.ics -> /webroot/protected/cals/maincal.ics
lrwxrwxrwx 1 myself myself 66 relmaincal.ics -> ../../../protected/cals/maincal.ics
Ok, so here's what happens:
less maincal.ics works on shell
less relmaincal.ics fails with 'relmaincal.ics: No such file or directory' (even if shell autocompletion for the relative path did work during the execution of the symlink command!)
When you open phpicalendar now, it will render mycal.ics, mycal2.ics and testcal.ics (and they will work)
however, maincal.ics and relmaincal.ics will not be parsed or displayed
Now - this could be that PHP cannot resolve symlinks; however I speculate that the situation is this:
When I do less maincal.ics - it is myself who is user, who has read permission for /webroot/protected/cals
phpicalendar (so Apache webserver user) can otherwise also access /webroot/protected/cals as read-only, when given 'hardcoded' path
phpicalendar is also capable of reading local symlinks fine
Thus, I suspect, that the problem is: when trying to read the symlinks to protected cals, the user that is visible to the shell during that operation is Apache web user, which then doesn't get permissions to access a symlink to the protected/cals location!
The thing now is - I can easily copy the .ics files locally; however they are being changed by someone else, which is why I'd have preferred a symlink.
And my question is: can I do some sort of trickery, so that when phpicalendar/Apache tries to access a symlink to protected/cals, it 'thinks' that it is a local file - and otherwise, the contents of the protected/cals file are being 'piped' back to phpicalendar/Apache?? I guess I'm thinking something in terms of:
$ mkfifo mypipe
$ ln -s mypipe testpipe.ics
$ cat ./testpipe.ics # in one terminal
$ cat /webroot/protected/cals/maincal.ics > mypipe # in other terminal
... which would otherwise (I think) handle the permissions problem - except that, I don't want to cat manually; that would be something that would have to be done in the background, each time an application requests to read testpipe.ics:)
Well, thanks in advance for any comments on this - looking forward to hearing some,
Cheers!
Umm, I really doubt that the account the web server runs under can read anything under /root. That directory is usually mode 0700, user root, group root, or something very similar to that - meaning no non-root access is allowed. If you're running the web server as root, file read permissions are the least of your problems...
Your best bet then would be to place the read-only calendar files somewhere publicly available, and symlink to that location from wherever under /root you want to be able to access them.
Start by checking whether the Apache user can view your calendars:
you#host $ sudo -i -u <apache-user> -s /bin/bash
apache#host $ less /root/protected/cals/maincal.ics
I am running apache with mod mono and my asp.net app is using mono sqlite as its db. When i refresh the page twice i get the DB is locked error. The folder it is in is chmod 777. The webapp is creating sqlite.db and sqlite.db-journal but it doesnt seem to be able to delete the journal. Also it has problems when i load the page once. It definitely seems to be a permission problem.
i'm confused. What permissions do i need to set these? i tried precreating the files using 777 and had no luck.
-edit- I didnt find a solution however i thought how silly i was being since i was planning to use mysql for my webapp. So i just ported the code and i no longer had issues.
When creating/deleting a file the directory permission matter.
So, if you really want that, you have to set the containing directory's permissions to 777.
Sample:
$ ls -la
total 21
dr-xr-xr-x 2 me me 1024 May 22 19:19 . #no write permissions to directory
drwxrwxrwt 21 root root 19456 May 22 19:19 ..
-rwxrwxrwx 1 me me 0 May 22 19:19 abc #all permissions to file abc
$ rm abc
rm: cannot remove `abc': Permission denied #abc has 777, but deleting doesn't work
$ chmod 777 . #change directoy's permissions
$ rm abc #now removing works
$ ls #file abc is gone
The reason is that when you delete a file, you actually modify the directory and not the file itself.
Think of a hard link: The file itself will not change when you delete one hardlink to it, but the directory changes.
Sounds more like one instance of the session in apache is blocking the other session, i.e. has the db file open exclusively. Try to let the database(model) run as a singleton (or similar) which all sessions access.