[P]Delete

Many times we need to know how much  RAM  or  virtual memory  a process is using. Suppose you are deploying a  website  on  server  and you want to configure Maxclient  on  apache  configuration file and to set that first you need to know how much memory apache process is taking. In this blog I will explain how we can check memory details on  linux  server. In linux virtual memory is the sum of swap memory and RAM memory. Virtual memory = swap memory + RAM memory To check memory usage of a process we first need to know its id(pid), for that run following command in  terminal # ps -A It will show you all the running process on system, select pid of the process for which you want to check memory usage. Now run following command (replace pid with actual process number. # cat /proc/pid/status It will give output which include following terms(leave others), lets understand them: VmSize : Virtual memory siz...

Apache  is the most common and famous webserver. Everyone knows about apache and most of us also have hands on experience with apache. But few of us know that apcahe2 comes with 2  multi processing modules (MPMs): 1.  Prefork 2.  Worker What is the difference between this two? Prefork MPM  uses multiple child processes with one thread each and each process handles one connection at a time. Worker MPM  uses multiple child processes with many threads each. Each thread handles one connection at a time. On most of the systems, speed of both the MPMs is comparable but prefork uses more memory than worker. Which one to use? On high traffic websites worker is preferable because of low memory usage as comparison to prefork MPM but prefork is more safe if you are using libraries which are not thread safe. For example  you cannot use mod_php(not thread safe) with worker MPM but can use with prefork. So if you are using all thread safe lib...

If you have installed a new  apache  web  server ( prefork  MPM ), planning to launch an online application and exptecting good amount of traffic then before going live, check apache settings for prefork mpm otherwise your server will not able to serve even 20-30 users. Why, becouse apache default setting are not optimized for high traffic, you have to adjust prefork settings based on your application and hardware(RAM,Swap etc). Before I will start explaining prefork configuration, if you are not aware of prefork mpm or how to check apache memory details then read following blogs before proceeding further: Prefork Vs Worker Apache Memory Details Open your apache config file or run following command gedit /etc/apache2/apache2.conf Search prefork setting block, which look like this ? 1 2 3 4 5 6 7 <IfModule mpm_prefork_module> StartServers 5 MinSpareServers 5 MaxSpareServers 10 MaxClients 150 MaxRequestsPerChild 0 <...

Domain: hifisenses.com Email user: admin@hifisenses.com IP Server: - Websites: 54.169.2.144 - Mail Server: 23.229.189.137 Create A record: Hifisenses.com  Mail.hifisenses.com Create MX record Test:

# sh cron/vtigercron.sh We tried to run vtigercron.sh then get the log below. -------------------------------------------------------------- [INFO]: Workflow - not ready to run as the time to run again is not completed [INFO]: RecurringInvoice - not ready to run as the time to run again is not completed [INFO]: SendReminder - not ready to run as the time to run again is not completed [INFO]: ScheduleReports - not ready to run as the time to run again is not completed [INFO]: MailScanner - not ready to run as the time to run again is not completed [INFO]: Scheduled Import - not ready to run as the time to run again is not completed -------------------------------------------------------------- Solution: Follow the steps -  - Go to vtlib/Vtiger/Cron.php - Go function - isRunnable() - after  if (!$this->isDisabled()) { - add  return true;  Then run the cron script again. # sh cron/vtigercron.sh

vi/vim FAQ: Can you share some example vi/vim  delete  commands? The vi editor can be just a little difficult to get started with, so I thought I'd share some more vi commands here today, specifically some commands about how to  delete  text in vi/vim. vi delete commands - reference A lot of times all people need is a quick reference, so I'll start with a reference of vi/vim delete commands: x - delete current character dw - delete current word dd - delete current line 5dd - delete five lines d$ - delete to end of line d0 - delete to beginning of line :1,.d delete to beginning of file :.,$d delete to end of file If those don't make sense on their own, the next sections will provide a brief description of each vi delete command. vi  delete character  command When you're in command mode in the vi editor (just hit the [Esc] key and you'll be there), and you want to delete the character at the current cursor position, just use the  v...

I create new server with 10GB of HDD, but when i check on the command line, the root space only show 6GB. I'm using t2.micto and Redhat 7.0, disk type: XFS. - xvda1: boot partition - xvda2: root partition Fix Step: We have instance A with the volume VA. 1) Stop the current instace A 2) Snapshot the current volume VA of the instance A 3) Start the instance A 4) Create new volume with 25GB by using the snapshot of volume VA then we have new volume VB 5) Attach the new volume VB to the instance A as default (/dev/sdf) 6) From the ssh console, i use the lsblk command to list the disk. # lsblk 7) Using the xfs_repair to repair the /dev/xvdf2 ( yum install xfsprogs) # xfs_repair /dev/xvdf2 8) Continue as the image below 9) Remove the /dev/xvdf2, remember the start of this disk then we will create the new one with the same. 10) Using XFS command to repair the /dev/xvdf2 again. # xfs_repair /dev/xvdf2 11) Use the lsblk co...

Network Based Application Recognition (NBAR) is really a great idea, i know its not new one but worked for most of the purposes like blocking bit torrent traffic, mp3 and many more bandwidth wasting things. The resources provided here assist you in configuring your network to provide the appropriate level of service to these applications.You can use access control list to do these tasks but that’s a very old technique and there are many loop holes that you have to take care seriously. Like you can’t check and block what port a bit torrent client is using. This means you can’t depend on access-lists being able to block the traffic. Cisco’s  NBAR  users packet inspection to determine what traffic class a data stream belongs to. With NBAR, it’s no longer necessary to know what ports an application is using. You need to take care three steps and you goes on air to detect if any of your user is using bit torrent to waste your valuable bandwidth and you even can block. Create a...

To find the values or exact names of what you would like to monitor: root@host:~# snmpwalk vpn.openforce.com -v 2c -c mtt |grep -i ifinoctet IF-MIB::ifInOctets.1 = Counter32: 2216 IF-MIB::ifInOctets.2 = Counter32: 2909800100 IF-MIB::ifInOctets.3 = Counter32: 0 IF-MIB::ifInOctets.4 = Counter32: 948093493 IF-MIB::ifInOctets.5 = Counter32: 252207088 IF-MIB::ifInOctets.6 = Counter32: 0 IF-MIB::ifInOctets.7 = Counter32: 0 IF-MIB::ifInOctets.8 = Counter32: 0 IF-MIB::ifInOctets.9 = Counter32: 0 IF-MIB::ifInOctets.10 = Counter32: 0 IF-MIB::ifInOctets.11 = Counter32: 0 IF-MIB::ifInOctets.12 = Counter32: 0 IF-MIB::ifInOctets.13 = Counter32: 0 IF-MIB::ifInOctets.14 = Counter32: 0 IF-MIB::ifInOctets.15 = Counter32: 0 IF-MIB::ifInOctets.16 = Counter32: 0 IF-MIB::ifInOctets.17 = Counter32: 0 IF-MIB::ifInOctets.18 = Counter32: 0 IF-MIB::ifInOctets.19 = Counter32: 0 IF-MIB::ifInOctets.20 = Counter32: 0 IF-MIB::ifInOctets.21 = Counter32: 258005245 To find the OID of the item you want to get: root@...

Method 1: Use a Hard Drive Partition for Additional Swap Space If you have an additional hard disk, (or space available in an existing disk), create a partition using fdisk command. Let us assume that this partition is called /dev/sdc1 Now setup this newly created partition as swap area using the mkswap command as shown below. # mkswap /dev/sdc1 Enable the swap partition for usage using swapon command as shown below. # swapon /dev/sdc1 To make this swap space partition available even after the reboot, add the following line to the /etc/fstab file. # cat /etc/fstab /dev/sdc1 swap swap defaults 0 0 Verify whether the newly created swap area is available for your use. # swapon -s Filename Type Size Used Priority /dev/sda2 partition 4192956 0 -1 /dev/sdc1 partition 1048568 0 -2 # free -k total used ...

Microsoft's SQL Server Management Studio will connect by default to port 1433 and there's nowhere in the connect dialog to specify a different port from the default. To connect using a different port specify the servername, a comma, and then the port number as shown in this post. Connect using a different port using a comma The connection dialog in the SQL Server Management Studio client is shown in the screenshot below. Normally you would just type the server name into field but to specify a different port use a comma then the port number. The example screenshot above shows " 192.168.50.166\SQLSERVER2012 " as the instance name and "port" where the port would be. 192.168.50.166\SQLSERVER2012,1343 Then specify the login credentials, click the connect button, and assuming everything is correct it should then connect to the SQL Server. Setup specific port for SQL Server: Link: http://msdn.microsoft.com/en-us/library/ms177440.aspx

Preface The purpose of this post is to provide guidance to Snort users who would like to try out Snort 2.9.7.0 and the OpenAppID features that it comes with. It is not intended to guide the reader through setting up Snort from scratch, there are plenty of docs on how to set up Snort at  http://www.snort.org/docs. Snort Before we can download the latest Snort source code and compile it, we have a new prerequisite to fulfill before we can compile Snort. You'll need to install  Luajit , which is used to define application detectors with the new OpenAppID. Step #1, Prep the system. You’ll need to download the following files from  snort.org download page : *   daq-xxx.tar.gz *   snort-2.9.7.0_xxx.tar.gz *   snort-openappid-detectors.xxx.tgz *   snortrules-snapshot-xxx.tar.gz Step #2, Install Snort requirements On my Ubuntu system this was as easy as the following command. #   sudo apt-get install openssl libssl-dev build-essential g++ flex bison ...