Insert/Add String to Beginning of a File

Inserting a String to Beginning of File

  1. Suppose you had a text file with the contents and you wanted to insert a string to the beginning:
    1st line
    2nd line
    3rd line
  2. Run the command:
    sed -i '1s/^/<add text > \n/' file.txt
  3. Now the file will look like this:
    Top of the file!
    1st line
    2nd line
    3rd line

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CLEANING UP THE ZABBIX DATABASE

My Zabbix database size increased a lot in the last few months and since my disk was running out space, I decided to clean up the old events from the database. Looking at the database tables, the biggest one was  history_uint , which holds the items history data – over 400 millions of records and over 30 Gb of disk space before the clean up. Since deleting the old records from this table directly would be a very slow process, I decided to create a new table and insert the latest records from the  history_uint  table and then just replace the old table with a new one. Since this is not an offical procedure, use it at your own risk. Environment: Zabbix v2.2 MySql 5.1 – InnoDB with  innodb_file_per_table=ON Step 1 – Stop the Zabbix server Step 2 – Open your favourite MySQL client and create a new table CREATE TABLE  history_uint_new  LIKE  history_uint; Step 3 – Insert the latest records from the  history_uint  table to the  history_uint_new table First you need to de
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Configuring DHCP Relay service on the FortiGate unit

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WAN link load balancing

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W A N link load balancing In the same way that incoming traffic can be load balanced, outgoing or WAN traffic can also be load balanced and for the same three reasons. 1 .  Reduce the places in the work flow where a single point of failure can bring the process to a halt. 2 .  Expand the capacity of the resources to handle the required workload. 3 .  Have it configured so that the process of balancing the workload is automatic. Often, it can be just as important for an organizations members to be able to access the Internet as it is for the denizens of the Internet to access the Web facing resources. There is now a  WA N Load Balancing  feature located in the  N e t w o r k  section of the GUI (“WAN LLB”). As part of the new WAN Load Balancing feature, the FortiOS 5.2  R ou t e r > Static > Settings  GUI page has been removed. WAN Load Balancing should be used instead of the 5.2  E C M P Load Balancing Method  settings. The 5.2  L i n k Health Monitor  definitions
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