Victory goes to the player who makes the next-to-last mistake
November 20, 2019 Leave a comment
I faced this issue while distributing the downloaded packages in cloudera manager.
The solution that worked for me is to add the IP Address – Hostname mapping in all the /etc/hosts files of all the cloudera manager server and agents
/etc/hosts 192.168.0.101 cdhdatanode1
November 20, 2019 Leave a comment
If you are facing an error like “Failed to collect NTP metrics”. The following solution might help you. This is because of the lack of ntp server in the server. The below solution will work for CentOS/RHEL systems. NTP will sync the system time with the network time.
yum install ntp systemctl enable ntpd systemctl restart ntpd
November 15, 2017 Leave a comment
The installation of pycrypto package may fail with errors like
“error: no acceptable C compiler found in $PATH”
“RuntimeError: autoconf error”
“fatal error: Python.h: No such file or directory”
” #include “Python.h”
^
compilation terminated.
error: command ‘gcc’ failed with exit status 1″
The solution for this issue is to install the following dependent packages.
yum install gcc yum install gcc-c++ yum install python-devel pip install pycrypto
April 5, 2016 Leave a comment
Amazon Web Services is one of the most popular cloud service providers. I am a customer of Amazon. I like the services provided by Amazon very much. Compared to other cloud service providers AWS is simple, secure and advanced. I use EC2 machines for my project related activities as well as my personal experiments. Since I mostly work on open source software, 99.99 % of my EC2 instances are Linux instances. The only way to access these instances is through ssh. I use putty as the ssh client. If something happens to the ssh server, we will not be able to access the server. Sometimes the ssh server crashes due to overload. This can be resolved by rebooting the instance.
Sometimes because of wrong configs in the sshd config file, the ssh server may stop. The ssh server will not start until we make that file proper and restart the service. But for making these changes we have to access the machine.
By default we don’t have direct root login into the machine. We usually login to one user which is a sudo user and using sudo privileges, we access the root. If something happens to the sudoers file or if some wrong entry made in sudoers file, the root access will be revoked.
These are some of the commonly occurred situations where users loose access or super user privilege in the ec2 machine. Most of the users terminate and leave the instance in this situation.
If the instance is an EBS backed instance, we don’t have to terminate and leave the machines in this kind of situations. We can recover these instances. It is simple and can be done in few steps. If the instance is with ephemeral storage, we cannot do anything, because shutting down will clear all the data in the instance.
This should fix the problem.
