/ - rtt - IT Resource

  • Linux What is umask (user mask) for file and directory creation permissions and how to calculate umask and change the defaults


    umask are the default permissions that are applied when a file or directory are created.  To see this in action simply just "touch filename" or "mkdir somedir" and you'll see what default permissions are applied. The first thing I always tell people you should know is to NEVER change the defaults unless you are making them more restrictive.  But they work well and if you change the defaults you could end up creating a file without permission to read........
  • Linux Permissions and Groups Real Usecase for Group Access


    I have a directory structure which the primary user needs full access on but wanted a user to access only a specific directory within the main directory (so they could write in there only and nowhere else). Here's what I did: [root@compevo8001 dllnow]# ls -alh drwxrwxr-x  2 someuser software  4.0K Oct 19  2017 ExpireYMD-2017-11-20 drwxrwxr-x  2 someuser software  4.0K Nov 19  2017 ExpireYMD-20........
  • gvfs mount in /run/user cannot be accessed or displayed wrong permissions


    The folder contents could not be displayed Backend currently unmounting drwx------ 10 userhere group  260 Aug 23 19:40 .. ??????????  ? ?   ?      ?            ? sftp:host=192.168.8.80,user=adhoc ls: cannot access 'sftp:host=192.168.8.80,user=adoc': Input/output error $ ps aux|grep fuse one       253........
  • VSphere InternalServerError - Error When Adding Permissions


    InternalServerError (com.vmware.vapi.std.errors.internal_server_error) => { messages = [LocalizableMessage (com.vmware.vapi.std.localizable_message) => { id = vapi.bindings.method.impl.unexpected, defaultMessage = Provider method implementation threw unexpected exception: com.vmware.vapi.std.errors.InternalServerError, args = [com.vmware.vapi.std.errors.InternalServerError] }], data = <null> } I was getting the........
  • Database Error One or more of the WHMCS database tables appear to be either missing or corrupted. Please check and repair. - WHMCS Solution


    Database Error One or more of the WHMCS database tables appear to be either missing or corrupted. Please check and repair. This error can be misleading especially if you know you are using a known good backup or restoration of the WHMCS database.  The error can also be that the user lacks permissions to read and write to the database. To check to this in MySQL shell: GRANT read,write to dbusername@localhost on dbna........
  • postfix errors fatal: no SASL authentication mechanisms /usr/libexec/postfix/smtpd: bad command startup -- throttling solution


    Jul  3 22:12:17mailserver postfix/smtpd[6195]: fatal: no SASL authentication mechanisms Jul  3 22:12:18mailserver postfix/master[4881]: warning: process /usr/libexec/postfix/smtpd pid 6195 exit status 1 Jul  3 22:12:18mailserver postfix/master[4881]: warning: /usr/libexec/postfix/smtpd: bad command startup -- throttling This only ever happens in my experience when the authentication method is actually Dovecot.  Usually the problem........
  • error: Could not locate RPC credentials. No authentication cookie could be found, and no rpcpassword is set in the configuration file Bitcoin Litecoin Error


    error: Could not locate RPC credentials. No authentication cookie could be found, and no rpcpassword is set in the configuration file This is usually because the .cookie file cannot be read by the user you are running Litecoin or Bitcoin client/daemon as. You can adjust the permissions of the file so that the user or group they are apart of has read permissions.  ........
  • Track 01: 34 of 1726 MB written (fifo 100%) [buf 99%] 3.6x.Errno: 5 (Input/output error), write_g1 scsi sendcmd: cmd timeout after 1.897 (40) s CDB: 2A 00 00 00 44 A9 00 00 1F 00 resid: 6144 cmd finished after 1.897s timeout 40s write track da


    These errors believe it or not are simply because of not being the root user or running with sudo! However if you didn't know to try as root you'd think there was a problem with your burner or disc  Essentially it looks like without root you cannot send the required scsi commands to continue writing.  I think cdrecord should have built-in tests or safeguards to see if it has the permissions to run the required commands. I guess for more advanced users the idea is simila........
  • xdebug easiest howto get going


    Just make sure you have php-xdebug installed and edit your php.ini: [xdebug] xdebug.profiler_enable = 0 xdebug.profiler_enable_trigger = 1 xdebug.profiler_output_dir = "/tmp/xdebug/" xdebug.output_name = "cachegrind.out.%t-%s" Also make and set permissions on /tmp/xdebug: mkdir /tmp/xdebug chmod 777 /tmp/xdeb........
  • sshd[10470]: Authentication refused: bad ownership or modes for directory /root


    This can be a case of bad permissions or modes as the error says.  Normally one would assume permissions but often a script may change ownership of /root to something else. This was the case half the time I've encountered this. So in short make sure ownership is correct chown -R root.root /root........
  • Centos cannot login by console or ssh session closed immediately


    In my case I could login with the initial install but I rsync'd everything over while preserving ownership and permissions to another RAID partition and booted from that.was fine before. The problem is that you are kicked out the second you login and the problem was SELINUX for some reason (perhaps it noticed something strange when it was moved to the new partition) login: pam_unix(login:session): session opened for user root by LOGIN(uid=0) login: ROOT LOG........
  • clamav freshclam out of date won't update solution


     freshclam ERROR: Can't open /var/log/clamav/freshclam.log in append mode (check permissions!). ERROR: Problem with internal logger (UpdateLogFile = /var/log/clamav/freshclam.log). Tue Oct 13 13:49:35 2015 -> WARNING: Incremental update failed, trying to download daily.cvd Tue Oct 13 13:49:35 2015 -> WARNING: Can't download daily.cvd from db.local.clamav.net Tue Oct 13 13:49:35 2015 -> Trying again in 5 secs...........
  • Vbox/Virtualbox devices grayed out for non-root user solution


    <p>It is a permissions issue that is hard to fix.</p> <p><strong>All but one USB device is greyed out.</strong></p> <p>I am already a member of &quot;vboxusers&quot;</p> <ul> <li>I have already enabled and disabled USB support for the guest.</li> <li>I have already reinstalled the latest VBOx guest editions</li> <li>If running as root it all works fine</li> <li>Changing........
  • phpBB guests unable to view forums without logging in Anonymous account solution


    This is still a weird quirk about phpBB, you can allow everyone+guests to see a forum. What also controls the first layer is this weird built-in "Anonymous" account.  You have to actually give that account specific rights to view all the forums or otherwise the above will happen and you'll wonder why your group permissions don't seem to apply. ........
  • VBulletin Enhanced Captcha / RegSecure not showing/working images solution.


    This happened after a customer migrated their hosting and the issue was being unable to access PHP sessions. Warning: session_start(): open(/var/lib/php/session/sess_3e0oms763m6mrqekdnnmodlhs3, O_RDWR) failed: Permission denied (13) in /register.php(202) : eval()'d code on line 1 Solution: (use the correct ownership/permissions) chown apache.apache -R /var/lib/php........
  • MySQL Error : Table 'datastore' is read only Error Number : 1036 solution


    This happens because of a permissions or ownership issue. Generally /var/lib/mysql should be all owned by mysql.mysql (check that). To fix it use chown -R mysql.mysql /var/lib/mysql Also make sure the files are at least readable and writable by mysql (eg. 700).........
  • Joomla Error - JFolder::create: Could not create directory


    JFolder::create: Could not create directory Plugin Install: Failed to create directory:   This can occur when trying to upload content or when installing themes/templates. It's usually not a permissions issue per say but doing a 777 (which is very insecure) will fix it.  But the real problem solution is that the owner of the files is different than the owner of the Apache process/server. Eg. if your Apache is running as user "apache........
  • Directadmin Enable SSL


    It's really silly how DA doesn't enable SSL by default but is otherwise a stable, fast and secure control panel. Here's a copy and paste way of enabling SSL for Directadmin in just a few seconds: *setup SSL openssl req -x509 -newkey rsa:1024 -keyout /usr/local/directadmin/conf/cakey.pem -out /usr/local/directadmin/conf/cacert.pem -days 9999 -nodes That creates the public certificate and private key pair in the location Directadmin expects to fi........
  • LOG: MAIN PANIC failed to expand condition "${if eq {$authenticated_id}{}{0}{${if eq {$sender_address}{$local_part@$domain}{0}{${if match{$received_protocol}{N^e?smtps?a$N}{${perl{checkbx_autowhitelist}{$authenticated_id}}}{${if eq{$received_prot


    I experienced this with CPanel's Exim after an auto-update (a Google of this error produces lots of complaints with few clear solutions).  In this case I'll put the solution at the top. Run /scripts/buildeximconf to rebuild the Exim config and it should be fine after that.   mail -vs "from test" user@dest.com < .bash_history LOG: MAIN   cwd=/root 4 args: send-mail -i -v user@dest.com LOG: MAIN   &........
  • Drupal/MySQL database error: PDOException: SQLSTATE[42000] [1044] Access denied for user 'db_user'@'localhost' to database 'dbname' in lock_may_be_available() (line 167 of /home/user/public_html/includes/lock.inc).


    PDOException: SQLSTATE[42000] [1044] Access denied for user 'db_user'@'localhost' to database 'dbname' in lock_may_be_available() (line    167 of /home/user/public_html/includes/lock.inc).   The username and password were correct but some reason CPanel added the user with no permissions!   Edit the user's permissions to include "All" from Cpanel or MySQL and that is the solution.........
  • iPhone Restore/Backup Location of Notes and Contact/Address Book


    *Make sure that the ownership is 501.501 or mobile.mobile when copying back (especially if using ssh or sftp as root on the iPhone) otherwise things will break.  Eg. the contacts will be blank even after trying to update due to incorrect ownership/permissions. iPhone Notes Location/Restore: /private/var/mobile/Library/AddressBook AddressBookImages.sqlitedb  AddressBook.sqlitedb Once you restore the contacts and restar........
  • samba/smbd connection to share problems and solutions


    I'll start by showing some problems in the logs: [2011/08/07 16:22:06,  0] param/loadparm.c:8569(process_usershare_file)   process_usershare_file: stat of /var/lib/samba/usershares/movie failed. Permission denied [2011/08/07 16:22:06,  1] smbd/service.c:676(make_connection_snum)   create_connection_server_info failed: NT_STATUS_ACCESS_DENIED That means you don't have permission to access the fi........
  • vnstat setup guide/tutorial


    yum -y install vnstat chown nobody.nobody -R /var/lib/vnstat/ #replace venet0 below with your desired interface sudo -u nobody vnstat -u -i venet0 #edit: vi /etc/sysconfig/vnstat #VNSTAT_OPTIONS="-i venet0" # only use the sed below if you are using venet0 instead of eth0 or replace accordingly sed -i 's/eth0/venet0/g' /etc/sysconfig/vnstat   [root@monitor]# yum install vn........
  • phpMyAdmin - Error Cannot start session without errors, please check errors given in your PHP and/or webserver log file and configure your PHP installation properly.


    The fix for this was setting the correct permissions in /var/lib/php, it needs to be "root.root" And /var/lib/php/session needs to be "root.apache" to work properly. After that I was able to login to phpMyAdmin as normal.  This whole thing happened because I accidentally changed all of /var/lib to root.root.........
  • MYSQL Error Can't find file: './wf/Sessions.frm' (errno: 13) Solution


    mysql errors even though these files do exist: 110405 13:21:37  InnoDB: Operating system error number 13 in a file operation. InnoDB: The error means mysqld does not have the access rights to InnoDB: the directory. InnoDB: File name ./ibdata1 InnoDB: File operation call: 'open'. InnoDB: Cannot continue operation. 110405 13:26:15  InnoDB: Operating system error number 13 in a file operation. InnoDB: The error means my........
  • monit example tutorial how to enable status checking and manipulation


    You need to enable the httpd daemon with monit to actually view the status and control, it's not only for the web interface since the httpd is the ONLY way of controlling monit and viewing the status. monit monitor all will also reinstate disabled services if they've timed out too much.  Just restarting the service will do nothing to re-monitor a service that monit has stopped monitoring due to too many failures. *Also note that /etc/monit.conf i........
  • Drupal 6.2 Install and how to move install to root/non-subdirectory


    drup 6.2 install $cd drupgoodinst3883/ [ drupgoodinst3883]$ ls CHANGELOG.txt  cron.php  index.php          INSTALL.pgsql.txt  INSTALL.txt  MAINTAINERS.txt  modules   robots.txt  sites   update.php   xmlrpc.php COPYRIGHT.txt  includes  INSTALL.mysql.txt  install.php        LICENSE.txt  misc  &........
  • Thunderbird/MBOX to IMAP/Maildir migration done easy with mb2md


    Convert MBOX Mail files into Maildir using Linux *You need perl an the TimeDate module Get the free Perl script mb2md from the project/author's site: wget http://batleth.sapienti-sat.org/projects/mb2md/mb2md-3.20.pl.gz gunzip mb2md-3.20.pl.gz #remember you need timedate or you'll get this error: ./mb2md-3.20.pl Can't locate........
  • Apache Forbidden You don't have permission to access / on this server.


    Forbidden You don't have permission to access / on this server. [Sun Jan 23 15:28:12 2011] [crit] [client 96.44.31.12] (13)Permission denied: /www/vhosts/domain.com/httpdocs/.htaccess pcfg_openfile: unable to check htaccess file, ensure it is readable   Solution I've done a chmod 755 .htaccess and index.php and restarted Apache That wasn't the only issue, the issue was the httpdocs direc........
  • Cygwin and crontab backups via ssh/scp/rsync


    Install the "Editors" and "Net" groups that will give you rsync, ssh, ssh-keygen and cron. The trickiest thing that I keep forgetting about each time is you have to run "cron-config" which adds the cron service to Windows, and without doing that obviously no cron jobs will be run thus making automatic backups impossible. Warning about rsync/cygwin and using the -a archive switch. It's a good thing I caught this because it doesn't work ri........
  • rsync preserve attributes, permissions/ownership and times without being root non-root user


    One of the purposes of rsync is to backup whole filesystems and archive them but how can you do that properly and restore things to normal if all permissions and ownerships are not preserved from your root filesystem? It's not desirable to have everything running as root, especially not just for an rsync. The Easy rsync preserve permission solution for non-root users sudo is the answer and all you have to do is edit /etc/sudoers At the end o........
  • FUSE/Curlftpfs mount ftp account as drive partition in Linux


    This is a great way to use your ftp server space, for example on your web hosting account (although I believe many hosts don't allow storage like this), but if you have a VPS/Dedicated Server etc.., this would be perfect.  Imagine how easy it is to work with an ftp account that you can just mount as a normal partition or directory in Linux, it would be great for backups etc..   Name curlftpfs - mount a ftp host as a local directory Synopsis........
  • rsync my favorite/best/optimal default switches and options


    Not sure what rsync switches/options to use? rsync -PDrphogtl The short version would be: rsync -Pha I think these are really common sense options to use and probaby should be the default. Explanation of rsync switches P = display the progress D = hybrid of --specials and --devices so all special and device files will be copied as well. r = recursive (otherwise rsync won't copy files deeper than........
  • MySQL Error "ERROR 1045 (28000): Access denied for user"


    This happened with a select statement which writes the result to an external file.  I didn't remember the privilege "FILE" must be granted on *.* for this to work successfully, it wasn't actually an authentication issue as it implies since I was already in the SQL prompt and doing the query. SELECT some_id FROM sometable INTO OUTFILE '/tmp/result.txt'........
  • Viewing and Connecting to an SMB Samba Share on Windows/Linux/Unix


    This will give you the basic info needed to browse and connect to Samba shares from the command line.  From the GUI of Gnome or KDE etc, it is pretty standard and straight forward.  However, I've found very little guides on how to do it from the command line and if you're like me, a nerd who prefers command line for its simplicity and for remote use, this is the way to go. First get a list of all the Samba/SMB shares on the target. smbclient -L hostname........
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