/ - rtt - IT Resource

  • systemd management using systemctl and journalctl to check systemd logs


    systemd is like the service manager for your Centos and other modern Linux distributions (including Debian/Mint/Ubuntu) allows you to enable services, stop them, restart them, check their status and even reboot your system. The key commands or arguments you will use with systemctl are the following: Unit Commands:   list-units [PATTERN...]         List loaded units &nbs........
  • Maximum number of connections from user+IP exceeded (mail_max_userip_connections=10) Dovecot Solution


    This happens because Dovecot limits the maximum IMAP connections per IP to just 10.  This may be fine for a single client side IP but if an entire office or multiple users are behind one IP or a single heavy user is active then you will get bizarre errors in your e-mail clients such as "Password Incorrect" or similar in Thunderbird.  It won't be obvious on the client side as to what the problem is and they will probably just think the server is misconfi........
  • Unable to mount location Failed to retrieve share list from server: No such file or directory solution


    Cannot even "Browse Network" when clicking on "Windows Network" Unable to mount location Failed to retrieve share list from server: No such file or directory logs: [2017/02/14 00:16:44.271314,  0] ../source3/nmbd/nmbd.c:58(terminate)   Got SIGTERM: going down... [2017/02/13 17:35:41.797944,  0] ../lib/util/become_daemon.c:124(daemon_ready) &........
  • ERROR 2013 (HY000): Lost connection to MySQL server during query


    The solution is simple but strange, if you copy your /var/lib/mysql directory to another server and think it will work, be sure to check if you have /var/log/mysql and binary log files.  If you do, the server will not work and will give you errors like below and crash without the proper log files. UPDATE user SET password=password("newpass") WHERE user='root'; flush privileges; ERROR 2013 (HY000): Lost connection to MySQL server durin........
  • Centos and obfsproxy install errors


    pip install obfsproxy /usr/lib/python2.6/site-packages/pip/_vendor/requests/packages/urllib3/util/ssl_.py:90: InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#insecureplatformwarning.   InsecurePlatformWarning You are using pip version 7.1.0, however version 8.1.1 i........
  • HP XW9400 Motherboard In Desktop Issues


    Fortunately the format is EATX so an EATX case will work and the screw layout is standard. You will need to remove the HEX/TORX screws that are connecting the stock HP standoffs (meant to slide into an HP case). XW9400 Motherboard Issues Size: 12" x 13" Proprietary Power Connector Proprietary CPU Power Connector Proprietary Memory Power Connector Fan connectors are 4 pin so you will need some kind of adapter.........
  • How to Enable RDP Remote Desktop in Windows 2008 Server


    Start -> Administrative Tools -> Server Manager Under "Computer Information" click "Configure Remote Desktop". Under "System Properties" choose the type of "Allow connections" you want. That's all there is to enabling RDP Access in 2008 server.........
  • Apache SNI is not needed what is the issue?


    I read this article and still don't understand the issue. If I understand correctly the client negotiates after the first SSL connection and then gets the correct hostname and thus correct certificate. http://wiki.apache.org/httpd/NameBasedSSLVHostsWithSNI To their credit I know I'm not using SNI becuase I get this message in the Apache log :) [warn] Init: You should not use name-based virtual hosts in conjunction with SSL!! B........
  • Dell FS12-NV7 2U Server Information and Guide


    I've got one of these for testing projects from work at home and got more than I bargained for with the time I've spent on it due to the storage handing/Perc 6/i cards. My particular model came with the following: 2U Rack Mount Server with Rails 2xOpteron 2373 EE (Quad Core, there is a 6-core version that can be found at times) 16GB RAM 2 x 250GB Seagate SATA 2 x Dell Perc 6/i (horrible and a nightmare to work........
  • MySQL my.cnf Server How To Secure/Bind to Localhost and Prevent Outside Connections Solutions


    [mysqld] datadir=/var/lib/mysql socket=/var/lib/mysql/mysql.sock user=mysql # Disabling symbolic-links is recommended to prevent assorted security risks symbolic-links=0 bind-address=127.0.0.1 The key is "bind-address", set that to 127.0.0.1 and no one from outside the server can connect.........
  • ip_conntrack: table full, dropping packet. solution for Linux RHEL/Centos/Debian


    ip_conntrack: table full, dropping packet. A lot of clients I've seen have this issue, it really seems the default level is way too small.  Once this connection tracking table becomes full then packets get dropped which is obviously a bad thing. One thing to be mindful of though is that 350 bytes of memory are used per entry so there is some justification for not keeping it too high.  However, if you have multiple servers running or high traffic daemons........
  • How to view UDP and other protocol connections?


    netstat is weak and can't show udp connections and most other protocols, use "ss" which is what netstat should have been: The "-u" switch stands for udp, here's a list of other options: Usage: ss [ OPTIONS ]        ss [ OPTIONS ] [ FILTER ]    -h, --help        this message    -V, --version    output ver........
  • MySQL NEVER delete ib_logfile0 or ibdata1 or you'll lose data


    don't delete /var/lib/mysql/ib_logfile0 or ibdata1 or mysql won't restart I didn't realize they were internal and not part of replication like the relay files! /usr/libexec/mysqld: ready for connections. Version: '4.1.22-log'  socket: '/var/lib/mysql/mysql.sock'  port: 3306  Source distribution 110127 16:31:00 [Note] /usr/libexec/mysqld: Normal shutdown 110127 16:31:00  InnoDB: Starting shutdown...........
  • 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........
  • Picking an FTPD (vsftpd) Server in Linux Centos/Debian


    I decided on using yum to help me decide even though I normaly use proftpd I decided to see what else I could find. yum search ftp Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile  * rpmforge: ftp-stud.fht-esslingen.de  * base: mirrors.netdna.com  * updates: updates.interworx.info  * addons: yum.singlehop.com  * extras: mirrors.netdna.com rpmforge   ........
  • Problems surfing web/serving


    Problems surfing web/servingI noticed sometimes websites wouldn't load at random through a FreeBSD box and other systems on the same link didn't have the issue. I believe it is because of the low default limit of 128 TCP connections that caused the problem. It would also slow down any traffic that requires many connections such as Bittorrent. The fix is to increase the amount of connections to at least 1024 Edit [b:520b050d3e]/etc/sysctl.conf[/b:520b05........
  • Windows Media Player


    Windows Media PlayerJust one little question... and I'm not too sure if it falls into the hardware category... my Windows Media Player...or any music program for that matter buzzes at random and cuts out the music. But I don't think it's the music files themselves because I've put in regular CD's and have had the same problems. Any ideas on what the problem could be?Sounds like a soundcard/driver issue. I would recommend updating your soundcard driver i........
  • It's not all about the speed.


    It's not all about the speed.I'd also thought I'd mention that speed is not everything. Routing is the key, because if one router you hit is slow then it doesn't matter how fast your connection is. I have found that locally, Telus has much better routing than Shaw (although I have not yet tested their new DOCSIS network). There are also some countries such as Sweden that offer high speed connections, but the high speed only applies locally. The reason is that man........
  • Hard Drive Not Working/Not Detected By Your BIOS Anymore?


    I was starting to panic because suddenly my 1TB Seagate SATA drive wasn't working, I thought it was a BIOS issue because it seemed to have happened after I tried overclocking my Desktop too much. I tried powering down and waiting, but I still couldn't hear the drive spin up at all.  I tried a second 1TB hard drive and it wouldn't work either.  I checked all power connections again and again until one of the pins in the MOLEX connector popped completely loose. Th........
  • Have an OpenVZ VPS/Linux Virtual Private Server and nothing works right?


    A VPS Server I had just wasn't working right, code that I migrated there just wasn't working.  For example, it kept telling me the connection to the database was unsuccessful, halfway through iterating through results it already had. Then I realized it wasn't my code.  I checked my /proc/user_beancounters and found this: cat /proc/user_beancounters Version: 2.5 uid resource held maxheld barrier limit failcnt........
  • Samba SMB Error - Server not using user level security and no password supplied. tree connect failed: NT_STATUS_WRONG_PASSWORD


    Server not using user level security and no password supplied. tree connect failed: NT_STATUS_WRONG_PASSWORD That happens when trying to use smbclient to connect to a share.  The weird thing is that I can authnenticate just fine from Windows XP. It is partially my mistake, I forgot this share does have a password.  I've tried authenticating with the correct user and also with "Guest" because this works in Windows.  In Linux I ........
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