The Red Cross is probably the bestknown emergency relief organization in the countrybut theyre not necessarily the best. Accusations of mismanagement have. Linux System Administration and Configuration. Related Yo. Linux Configuration and Admin Tutorials. The Linux boot process. Quotas Assign disk resource limits to users or groups. Managing groups and user security Linux Networking tutorial. DHCP Server tutorial. NIS Server Client configuration tutorial. Sheet1 1100000217 Mookodi Business Enterprise BBBEE certificate expired for this supplier 1100000239 Bytes Technology Group SA Pty Ltd 1100000249 Tshwane Metropolitan. Gpg Full Installer Of Red' title='Gpg Full Installer Of Red' />Configuring an internet web server. Apache, DNS, FTP. Internet Server Security. System optimization System re configuration Commands used to re configure video, keyboard, mouse, datetime, sound card, NIC, Printer. Installing a new kernel RPMYo. Linux Tutorials Index. Monitoring the system Basic command line pstree Processes and parent child relationshipstop Show top processesmpstat Report processors related statistics. Example mpstat AUbuntu install apt get install sysstatdstat generate system resource statistics report. Examples dstat a, dstat fUbuntu install apt get install dstatiostat Report CPU statistics and inputoutput statistics for devices and partitions. Report virtual memory statisticsstat display file or file system status. Example stat f devsda. NFS statisticsUbuntu install apt get install nfs common. Display Linux kernel version in use. Display Red Hat Linux Release. Tell how long the system has been running. Also number of users and systems load average. Show who is logged on and what they are doing. List all currently loaded kernel modules. Same as cat procmodulessbinrunlevel. Displays the systems current runlevel. Displayschanges the systems node name. Must also manually change hostname setting in etcsysconfignetwork. Command will change entry in etchostsservice. Red HatFedora command to display status of system services. Example service status all. Help service help. Also see ntpstat. GUIGraphical gnome system monitor. Operating system monitor and usage graphing. Graphical system monitor. Additional RPM package gkrellmps. D load meter. Very cool 3 D graphics. Operating system monitor load, memory, swap, net, disk,. List of tools. Process Management. Processes execute within their own process environment, they have their own memory, current working directory, priority, process ID, parent process ID and the file access privileges of the user ID under which they execute. The basic Linux monitoring commands such as pstree and ps auxw. Sometimes a process must be terminated. To terminate a process. Identify the process. OR. ps auxw. OR. Kill the process. This will perform an orderly shutdown of the process. If it hangs give a stronger signal with. This method is not as sanitary and thus less preferred. A signal may be given to the process. The program must be programmed to handle the given signal. See usrincludebitssignum. For example, to restart a process after updating its configuration file. HUP lt process id number. In the previous example, the HUP signal was sent to the process. The software was written to trap for the signal so that it could respond. If the software command is not written to respond to a particular. Identify all known signals fuser l. Process Monitoring and Management GUI Tools xosview Oldie but goodie. Su. SE. QPS See below. Also see the GUI tool QPS. Handles MOSIX cluster. This tool is outstanding for monitoring, adjusting nice values priorities. RPM available from this site. It is so simple to use, no instructions are necessary. It can monitor a program to make sure it isnt doing something bad. It is also reverse engineer what applications are doing and the environments. I love this tool Note The RPM provided was compiled for Red. Hat 7. x. For Red. Hat 8. 0 one must. QT library RPMs to satisfy dependencies. Xt 2. 3. 1 8. i. Then install qps rpm ivh qps 1. Note Fedora Core 3 rpm ivh qt. These older RH 8. AMD6. 4 Fedora Core 3 x. OS system. Configuring QPS to run applications against a process Select Command Edit Commands. Add. Description GDB. Command Line xterm T GDB C e gdb d directory where source code is located pidp. Description gdb. Command Line xterm T gdb c p e gdb procpexe p As issued in RPM. Description strace. Command Line xterm T strace c p e sh c strace f pp sleep 1. Try it with the process qps itself. Show output written by process. T strace c p e sh c strace f q e tracewrite pp sleep 1. Description truss Solaris command. Command Line xterm T truss C p e sh c truss f p p sleep 1. Process Priority Control. Multi tasking operating systems executes processes in a time slice fashion sharing the processing resources base on their current privilege. Privileges are not constant and elevate if they have not received an execution allocation in the processor after a given time. This is to ensure that all processes get executed regardless of priority although a process can get squeezed out of the time allocation alltogether if the system is overloaded. Higher priority processes may get more time allocated on the processor than a lower priority process but it is likely that the lower process will get some processor allocation. Many system process which manage the system environment execute at an elevated priority in order to guarentee that they get executed. User processes can have their priority elevated using the nice command. Nice values have a range from 2. Beware that if the priority is elevated higer than a system process, the behavior of the system may be compromised. Modify process scheduling priority. Lower scheduling priority runs slower and less likely to slow you down. Default for nice n is 1. Show default for any process nice executable. Shows nice value to be used if run. IPCs Semaphores, Shared Memory and Queues. Note that some processes may use Linux Inter. Process Communication or IPC. Identify the semaphores ipcsipcs q List share queues. Shared memory. ipcs s List Semaphores. Remove the semaphores ipcrm s lt ipcs id. Example If you are running Apache, you may see the following. DIR ipcs m Shared Memory Segments key shmid owner perms bytes nattch status 0x. Processes attached to open files or open network ports. The command lsof. List processes attached to a given file lsof filename. DIR lsof varlogmailmanqrunner. REG 3,5 6. 57 4. REG 3,5 6. REG 3,5 6. 57 4. REG 3,5 6. REG 3,5 6. 57 4. REG 3,5 6. REG 3,5 6. 57 4. REG 3,5 6. The process attached to an open file can be killed using the command. List all open files on system lsofLong list. List all files opened by user lsof u user id. The commands netstat punta and socklist will list open network connections. Use the command lsof i TCP port number to see the processes attached to the port. Example. rootnode DIR lsof i TCP 3. COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME. IPv. 4 7. 56. 00. TCP ldap LISTEN. IPv. TCP ldap LISTEN. IPv. TCP ldap LISTEN. IPv. TCP ldap LISTEN. IPv. TCP ldap LISTEN. This shows that the command slapd running under user id ldap. Restricting user resources ulimit bash shell command. Shell and process resources may be controlled and reported using the. Display the limits of a shell using the bash command. Limits can be set for the number of open files and. View file size limits ulimit f. See limits assigned in etcsecurity discussed below. Process Commands nohup run a command immune to hangups, with output to a non tty. Linux Commands to Monitor Memory Usage vmstat Monitor virtual memoryfree Display amount of free and used memory in the system. Also cat procmeminfopmap Displayexamine memory map and libraries so. Usage pmap pidtop Show top processessar B Show statistics on page swapping. Show system page size, page faults, etc of a process during execution. Note you must fully qualify the command as usrbintime to avoid using the bash shell command time. Running A Full Node Bitcoin. What Is A Full Node A full node is a program that fully validates transactions and blocks. Almost all full nodes also help the network by accepting transactions. Most full nodes also serve lightweight clients by allowing them to. If not enough nodes perform this. Many people and organizations volunteer to run full nodes using spare. Bitcoin to continue to grow. This document describes how you can. Costs And Warnings. Running a Bitcoin full node comes with certain costs and can expose you. This section will explain those costs and risks so you. Special Cases. Miners, businesses, and privacy conscious users rely on particular. This document does not. Bitcoin network in general. Please seek out assistance in the community if you need help. Do your own diligence to ensure who you get help from is ethical. Secure Your Wallet. Its possible and safe to run a full node to support the network and use. Bitcoin wallet. Please see the. Minimum Requirements. Bitcoin Core full nodes have certain requirements. If you try running a. If you can meet the following requirements, youll. Desktop or laptop hardware running recent versions of Windows, Mac OS. X, or Linux. 1. 45 gigabytes of free disk space. RAMA broadband Internet connection with upload speeds of at least 4. An unmetered connection, a connection with high upload limits, or a. Its common for full nodes on high speed connections to. Download usage is around 2. You can do. other things with your computer while running a full node. More hours would be better, and best of all would be if you can run. Note many operating systems today Windows, Mac, and Linux enter a. This is often the default setting on laptops and on. Mac OS X laptops and desktops. Check your screensaver settings. Possible Problems. Legal Bitcoin use is prohibited or restricted in some. Bandwidth limits Some Internet plans will charge an additional. Worse, some providers may terminate your connection without. We advise that you check whether your. Internet connection is subjected to such limitations and monitor your. Bitcoin Core before you reach your. Anti virus Several people have placed parts of known computer. Bitcoin block chain. This block chain data cant infect. Bitcoin Core. This problem mostly. Din Next Pro Condensed Medium Download Yahoo. Windows. Attack target Bitcoin Core powers the Bitcoin peer to peer. Bitcoin Core users in ways that will affect other things. Linux Instructions. The following instructions describe installing Bitcoin Core on Linux. Ubuntu 1. 6. 1. 0nstructions for Bitcoin Core 0. If you use Ubuntu Desktop, click the Ubuntu swirl icon to start the Dash and type term into the. Choose any one of the terminals listed Alternatively, access a console or terminal emulator using another. SSH on Ubuntu Server or a terminal launcher in an. Type the following line to add the Bitcoin Personal Package Archive. PPA to your system sudo apt add repository ppa bitcoinbitcoin. You will be prompted for your user password. Provide it to continue. Afterwards, the following text will be displayed Stable Channel of bitcoin qt and bitcoind for Ubuntu, and their. Note that you should prefer to use the official binaries, where possible, to. Launchpadthe PPA owner. No longer supports precise, due to its ancient gcc and Boost versions. More info https launchpad. Press ENTER to continue or ctrl c to cancel adding it. Press enter to continue. The following text with some variations will. CE5. E from hkp server keyserver. CE5. E public key Launchpad PPA for Bitcoin imported. Total number processed 1. RSA 1. Type the following line to get the most recent list of packages A large number of lines will be displayed as different update files are. This step may take several minutes on a slow Internet. To continue, choose one of the following options. To install the Bitcoin Core Graphical User Interface GUI, type the. Bitcoin Core GUI. To install the Bitcoin Core daemon bitcoind, which is useful for. Bitcoin Core Daemon section below sudo apt get install bitcoind. To install both the GUI and the daemon, type the following line and. GUI instructions and the daemon. Note that you cant run both the GUI. After choosing what packages to install, you will be asked whether you. Press enter to continue. Bitcoin Core GUITo start Bitcoin Core GUI, click the Ubuntu swirl icon to open the Dash. Bitcoin icon. You will be prompted to choose a directory to store the Bitcoin block. Unless you have a separate partition or drive. Ok to use the default. Bitcoin Core GUI will begin to download the block chain. This. step will take at least several days, and it may take much more time on. Internet connection or with a slow computer. During the. download, Bitcoin Core will use a significant part of your connection. You can stop Bitcoin Core at any time by closing it it will. After download is complete, you may use Bitcoin Core as your wallet or. Bitcoin network. Optional Start Your Node At Login. Starting your node automatically each time you login to your computer. The easiest way. to do this is to tell Bitcoin Core GUI to start at login. While running Bitcoin Core GUI, open the Settings menu and choose. Options. On the Main tab, click Start Bitcoin on system login. Click. the Ok button to save the new settings. The next time you login to your desktop, Bitcoin Core GUI will be. You have now completed installing Bitcoin Core. If you have any questions, please ask in one of Bitcoins many communities, such as Bitcoin Stack. Exchange, Bitcoin. Talk technical support, or the bitcoin IRC chatroom on Freenode. To support the Bitcoin network, you also need to allow incoming. Please read the Network. Configuration section for details. Bitcoin Core Daemon. If youre logged in as an administrative user with sudo access, you may. The steps in this section should be performed as the user you. Bitcoin Core. If youre an expert administrator, you can. Bitcoin Core. From the terminal, type It will print a message that Bitcoin Core is starting. To interact with. Bitcoin Core daemon, you will use the command bitcoin cli Bitcoin. Note it may take up to several minutes for Bitcoin Core to start. Verifying blocks. After it starts, you may find the following commands useful for basic. For example, to safely stop your node, run the following command A complete list of commands is available in the Bitcoin. When Bitcoin Core daemon first starts, it will begin to download the block. This step will take at least several days, and it may take much more time. Internet connection or with a slow computer. During the download. Bitcoin Core will use a significant part of your connection bandwidth. You can. stop Bitcoin Core at any time using the stop command it will resume from the. Optional Start Your Node At Boot. Starting your node automatically each time your computer boots makes it. The easiest way to do this. Bitcoin Core daemon from your crontab. To edit your. crontab, run the following command Scroll to the bottom of the file displayed and add the following line Save the file and exit the updated crontab file will be installed for. Now Bitcoin Core daemon will be automatically started each time. If youre an Ubuntu expert and want to use an init script instead, see. You have now completed installing Bitcoin Core. If you have any questions, please ask in one of Bitcoins many communities, such as Bitcoin Stack. Exchange, Bitcoin. Talk technical support, or the bitcoin IRC chatroom on Freenode. To support the Bitcoin network, you also need to allow incoming. Please read the Network. Configuration section for details. Other Linux Distributionsnstructions for Bitcoin Core 0. The following instructions describe installing Bitcoin Core using tools. Linux distributions. We assume you use a. Bourne like shell such as bash. Using any computer, go to the Bitcoin Core download page. In the Linux tgz section of the Download page, choose the. Linux install either 3. If necessary, move the file to the computer you want. Bitcoin Core. Optional Verify the release signatures.