After finishing my script from the previous post I thought there has to be a better way to write this and reduce the lines of code. Not that 5 separate lines is a lot. But, if the list of items to print grew larger say to 15 documents, and was in different subdirectories then it might get complicated. So, I set about trying to find a way to use the ForEach-Object cmd. After some trial and error I have come up with this.
$Directory = “\\SVR1\DATA\Reports\Trading\”
Get-ChildItem -path $Directory -recurse -include *.pdf | ForEach-Object {Start-Process -FilePath $_.fullname -Verb Print -PassThru | %{sleep 10;$_} | kill }
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PowerShell comparison operators -eq, -lt, -gt, -contains, -like, -match
If you are used to operators such as > or < or =, you have to do some rethinking. As with batch scripts, PowerShell uses abbreviations of the corresponding English words. -eq Equal -ne Not equal -lt Less than -le Less than or equal -gt Greater than -ge Greater than or equal You don’t need an if statement to test the result of a comparison operation. Without the if statement, the output of the comparison is, simply, TRUE or FALSE. Read More
Test filters using fail2ban
Whenever you add or change a filter you will want to test that the regular expressions are correct by running it over an existing logfile.
The tool for doing this is fail2ban-regex which is used as follows:
fail2ban-regex /var/log/fail2ban.log /etc/fail2ban/filter.d/fail2ban-smtp.conf
How to set Java Home path [linux]
Set JAVA_HOME / PATH for a single user
Login to your account and open .bash_profile file
$ vi ~/.bash_profile
Set JAVA_HOME as follows using syntax export JAVA_HOME=
export JAVA_HOME=/usr/java/jdk1.5.0_07/bin/java Read More
Postfix dkim and spf filtering
Installing OpenDKIM:
yum install opendkim
Create private and public key:
mkdir /etc/opendkim/keys/myhostname.lt /usr/sbin/opendkim-genkey -D /etc/opendkim/keys/myhostname.lt/ -d myhostname.lt -s default chown -R root:opendkim /etc/opendkim/keys/myhostname.lt chmod 640 /etc/opendkim/keys/myhostname.lt/default.private chmod 644 /etc/opendkim/keys/myhostname.lt/default.txt
Setting static IP in CentOS 7 Minimal Installation
In order to set the network adapter and get get CentOS to communicate on the network the Ethernet adapter will need to be configured. In this lesson I will set a static IP address for the network adapter. To view a list of your network adapters use the command ip addr.
The configuration file for the network adapter should be located at /etc/sysconfig/network-scripts/ifcfg-enp0s3. With the minimal installation of CentOS there are not many options available to configure the network adapter. One option is to use the vi editor or nano to configure ifcfg-enp0s3. Another option is to use the nmtui utility to edit the network adapter. Read More
Prevent DOS with iptables
Of course there are several types of DOS attacks , in this post I will demonstrating the use if iptables to limit the traffic on port 80.
The goal is to keep your web server “responsive” to legitimate traffic, but to throttle back on excessive (potential DOS) traffic.
In this demonstration iptables is configured :
- The default policy is ACCEPT (to prevent lockout in the event of flushing the rules with iptables -F).
- “Legitimate” traffic is then allowed. In this example I am allowing traffic only on port 80.
- All other traffic is then blocked at the end of the INPUT chain (the final rule in the INPUT chain is to DROP all traffic).
Show my ip
From terminal:
ip addr show eth0 | grep inet | awk '{ print $2; }' | sed 's/\/.*$//'
Example syntax for Secure Copy (scp)
scp allows files to be copied to, from, or between different hosts. It uses ssh for data transfer and provides the same authentication and same level of security as ssh.
Examples
Copy the file “foobar.txt” from a remote host to the local host
$ scp [email protected]:foobar.txt /some/local/directory Read More
CentOS timezone config
CentOS timezone config files and directories
- /usr/share/zoneinfo/ – The system timezone directory contains the files as per timezone name. For example, the file /usr/share/zoneinfo/America/New_York represents time zone for New York.
- /etc/localtime – It is a symlink to the file localtime or to the correct timezone file in the system located in /usr/share/zoneinfo/ directory.