With security being the focus these days, tools are more readily available for use to assist in remediation. One such tool is the OpenSCAP command-line tool. oscap is Security Content Automation Protocol (SCAP) toolkit based on OpenSCAP library. It provides various functions for different SCAP specifications (modules). This article is intended to identify the options that are available along with…
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The syslog server comes standard on CentOS/RHEL 7+ and is a system utility providing support for message logging. Support of both internet and unix domain sockets enables this utility to support both local and remote logging. With a couple of configuration changes can become a central monitoring server. There are syntax changes pre CentOS/RHEL 7.4 and CentOS/RHEL 7.4+ for semanage…
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Securing a CentOS 7 install doesn’t have to be tough. Code already exists, we just have to find it and execute it. Prerequisites yum install openscap scap-security-guide -y Verification The version of the scap-security-guide that was tested is 0.1.40. Version 0.1.43 has removed the DISA STIG from the CentOS guide ssg-centos7-ds.xml; however, there is a work-a-round. Article coming soon. scap-security-guide.noarch…
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I have an ansible playbook that has worked for months. It still works but, now has a DEPRECATION WARNING that looks ominous along with a python error. Problem BECOME password[defaults to SSH password]: [DEPRECATION WARNING]: The TRANSFORM_INVALID_GROUP_CHARS settings is set to allow bad characters in group names by default, this will change, but still be user configurable on deprecation. This…
Read More »While doing a little house cleaning on a VM, I discovered I was unable to reboot it. Basically, I had a logical volume that was rather large and wanted to remove it. I used the lvremove to remove the logical volume that spanned across two hard drives. There was no other logical volume on those drives. Shutdown the server and…
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VMware requires you to have an account to logon and download a free tool called “VMware OVF Tool”. That alone is not annoying. What is annoying is that the tool is extremely slow. There is a much faster way to create an OVA without the need of this tool. Using the ovftool is easy enough, the following is an example…
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I have been playing around with the buildSchedule.php component of NFL PHP Pick ‘Em as this is the component that makes it all possible to generate tables needed to create the SQL script to import into the new season. My previous post on this subject required a spreadsheet, which never really was necessary. Even though the output filename contains a…
Read More » NFL PHP Pick ‘Em is a free php web app that allows you to host a weekly NFL pick ’em football pool on your website. This fantastic tool replaced the use of spreadsheets. There was a time that this tool was not supported. However, I just checked out the www.phpickem.org website it is is updated for 2019. I wish I…
Read More »With CentOS/RHEL 6 there was a function called tmpwatch that was launched /etc/cron.daily/tmpwach This process has changed in CentOS/RHEL 7. There is a system target that runs daily: system-tempfiles-clean.timer. Although tmpwatch does a pretty good job in cleaning out the /tmp or /var/tmp files, it does not by default clean out the /tmp/systemd-private directories as these are secure. There are…
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For one reason or another it was difficult to find the “complete” answer to installing CentOS 7 on a GPT labeled disk. For the most part the answer was too complicated, incomplete, or inaccurate. After some trial and error the answer turns out to be a simple one. Process Basically, insert your CD/DVD for the install When presented with this…
Read More »Extend the swap size in a logical volume may be needed. Assume that there is a swap partition that requires an additional 1G of space. The following process should work on a CentOS 7 Linux install. Assuming that the disk space is available, use lvextend will add 1G, disable and flush out the existing swap space. It may take some…
Read More »A system that was a fresh installation of CentOS 7 Linux was just completed. After all the updates, the user began to install an application. After some time, the user logged out of the system and could not log back into it. As a root user, the administrator was unable to access the virtual machine even via console. This eliminated…
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The issue is that there may be a policy in place to prevent logons if there is any mount that is full. There are a couple of approaches towards resolution. Both approaches require a system shutdown. One approach requires access to the ISO, which leaves a plausible solution. reboot Hit CTL+X to edit the boot kernel ##CHECK THIS ONE, MIGHT…
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You have generated a SELinux human readable .te file and want to compile it into a .pp policy file. Prerequisites Only needed for sealert yum install setroubleshoot-server Troubleshooting This is a series of commands used to troubleshoot a recent zabbix-server service that would not start. It was the results of the ausearch that revealed the semodule command that differed from…
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In this exercise, Tomcat 9 will be installed with OpenJDK 8 using a self-signed certificate in a PKS12 keystore on a clean CentOS 7 Linux server using the Http11NioProtocol protocol. These are the steps. ######################################################################################## # Apache Tomcat 9 ######################################################################################## yum install wget vim net-tools firewalld unzip -y yum install java-1.8.0-openjdk-devel -y cd /opt/app wget http://us.mirrors.quenda.co/apache/tomcat/tomcat-9/v9.0.16/bin/apache-tomcat-9.0.16.tar.gz tar xzvf apache-tomcat-9.0.16.tar.gz ln…
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By combining the massively popular Elasticsearch, Logstash, and Kibana (what was the ELK Stack is now the Elastic Stack), Elastic has created an end-to-end stack that delivers actionable insights in real time from almost any type of structured and unstructured data source. There are many resources that offer installation procedures from simple to complex configurations. This is my take on…
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There are many articles that suggest that simply copying certain files from one CentOS to another CentOS server will be sufficient enough to migrate the user accounts along with their permissions and passwords. Other arguments suggest that certain files such as the passwd and shadow files should never be manually edited; but the caveat is that there is no “utility”…
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