A Technical I.T./DevOps Blog
Problem scenario
You have installed Chef on Ubuntu. You run this command:
sudo knife client list
You expect to see a list of Chef client nodes. But you see an error like this:
“ERROR: You authenticated successfully to https://<FQDN of Chef Server>/organizations/companynickname as <FQDN of Chef client node> but you are not authorized for this action
Response: missing read permission”
What do you do?
…
Problem scenario
You are trying to use Chef’s knife command. Every time you try to regenerate a key or delete a user, you get an error like this:
“ERROR: Failed to authenticate to https://continualintegration.com/organizations/contintnickname as contint with key /home/ec2-user/.chef/contint.pem
Response: Invalid signature for user or client ‘contint'”
What do you do?
Solution
1. Log into the GUI for Chef Manage.
…
Problem scenario
You have a desired configuration that you want implemented with Chef. You want a command to execute and a file to transfer via a Chef recipe or cookbook. You have installed Chef server on one server (see this posting if you want to do this) and Chef client on another (see this posting for installing Chef client). You want to use Chef for the first time doing something as an example.
…
Problem scenario
You are using RedHat Enterprise Linux in AWS. curl commands are not working. DNS names are not resolving accurately. For example, you try this command: curl http://icanhazip.com
You get this error:
“curl: (6) Could not resolve host: icanhazip.com; Unknown error”
How do you fix this to get curl commands to work (and make sure that FQDNs resolve properly)?
Solution
Do these four things:
1.
…
Updated 10/13/19
Problem scenario
You want to deploy Chef server to Linux in a standalone fashion. What do you do?
Solution
This solution has been tested to work with Ubuntu 16.04 Linux in AWS or Azure. This solution has also been tested to work with RHEL 7.4 in AWS.
#1 For a standalone deployment, you will need a server with 4 CPU cores and 4 GB of RAM according to this
…
Continue reading “How Do You Deploy a Standalone Chef Server to a Linux Server?”
Problem scenario
You live in an are that is susceptible to lightning (most of the world). You use a power strip or UPS with surge protection. Surge protection is made possible via a MOSFET (metal-oxide semi-conductor field effect transistor) that is destroyed when the power surges to potentially destructive levels. You do not have surge protection on the coaxial cable to the coaxial modem. You are concerned that if lightning were to strike,
…
Problem scenario
You want to copy files between RedHat Linux servers with adherence to security best practices. You try to use scp but you get “Permission denied.” What do you do to copy files in a secure way?
Solution
1. Verify you can SSH from one server to the other. For directions for setting up SSH in a cross-cloud environment, you may want to see this posting.
…
Continue reading “How Do You Use scp When You Get A “Permission Denied” Error?”
Problem scenario
When trying to install Apache Parquet on Ubuntu, you get this error:
Running python-snappy-0.5.1/setup.py -q bdist_egg –dist-dir /tmp/easy_install-SIHL_T/python-snappy-0.5.1/egg-dist-tmp-O8UnkU
WARNING: ‘.’ not a valid package name; please use only .-separated package names in setup.py
package init file ‘__init__.py’ not found (or not a regular file)
cc1plus: warning: command line option ‘-Wstrict-prototypes’ is valid for C/ObjC but not for C++
snappymodule.cc:31:22: fatal error: snappy-c.h: No such file or directory
compilation terminated.
…
Problem scenario
You have a web page from an .php file that includes HTML code. There are fields visible in the web page to the user. These fields accept text. You want the fields to not be blank; you want the fields to have suggested values of text in them. You want the data in the fields to be taken from the result of a SQL statement. How do you prepopulate text fields in a LAPP web page with values from SQL statements?
…
Continue reading “How Do You Prepopulate Text Fields in a Web Page with Values from a SQL Database?”
Problem scenario
You want to use Maven’s Apache Parquet plugin with Hadoop. How do you use these Apache technologies together?
Solution
1. Install HDFS. See this link if you are using Ubuntu. See this link if you are using a RedHat distribution of Linux. If you have more than one server and want a multi-node cluster of Hadoop, see this link for directions on how to deploy and configure it.
…
Continue reading “How Do You Configure Maven to Use an Apache Parquet Plugin?”