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Showing posts from April, 2019

Increase disk size for an EC2 instance in AWS

Increase disk size for an EC2 instance in AWS While using Amazon Web Services (AWS) you may find that, when using one of the Amazon Machine Images (AMIs) provided, you may run out of disk space. There does not appear to be any way to “resize” an Elastic Block Store (EBS) volume; however, you can create a new one based on an existing snapshot and replace the current drive with a larger one. I have provided the instructions for doing so below. Log into the AWS Management Console Make sure that the Instance that you wish to change is not currently running Navigate to Elastic Block Store > Volumes Check the box next to the Volume that needs more space Click the More… drop down list and select Create Snapshot Enter a Name and a Description Navigate to Elastic Block Store > Snapshots Monitor the progress of the Snapshot for completion Once complete, navigate back to Elastic Block Store > Volumes Click Create Volume Enter the desired size for the ne

RHEL / Centos Linux 7: Change and Set Hostname Command #Transient

RHEL / Centos Linux 7: Change and Set Hostname Command last updated January 6, 2018 in Categories CentOS , Linux , RedHat and Friends I ‘m a new RHEL (Red Hat Linux) and/or CentOS Linux 7 server user. How can I change the hostname in CentOS 7 using a command line option? On a CentOS Linux 7 server you can use any one of the following tool to manage hostnames:[donotprint][/donotprint] hostnamectl command : Control the system hostname. This is recommended method. nmtui command : Control the system hostname using text user interface (TUI). nmcli command : Control the system hostname using CLI part of NetworkManager. Types of hostnames The hostname can be configured as follows Static host name assigned by sysadmin. For example, “server1”, “wwwbox2”, or “server42.cyberciti.biz”. Transient/dynamic host name assigned by DHCP or mDNS server at run time. Pretty host name assigned by sysadmin/end-users and it is a free-form UTF8 host name for presentation to

Code For Maintenance Site #index.html #centos

Code For Maintenance Site #index.html #centos <!doctype html> < title >Site Maintenance</ title > < style > body { text-align : center ; padding : 150 px ; } h1 { font-size : 50 px ; } body { font : 20 px Helvetica , sans-serif ; color : #333 ; } article { display : block ; text-align : left ; width : 650 px ; margin : 0 auto ; } a { color : #dc8100 ; text-decoration : none ; } a :hover { color : #333 ; text-decoration : none ; } </ style > < article > < h1 >We & rsquo ; ll be back soon!</ h1 > < div > < p >Sorry for the inconvenience but we & rsquo ; re performing some maintenance at the moment. If you need to you can always < a href = " mailto:# " >contact us</ a >, otherwise we & rsquo ; ll be back online shortly!</ p > < p > & mdash ; The Team</ p > </ div > </ article

Troubleshooting DRBD #Centos #DRBD

Troubleshooting DRBD This article presents common DRBD problems and solutions. DRBD (Distributed Replicated Block Device) runs on the master and slave nodes only, and is responsible for mirroring the contents of a partition between master and slave. Typical problems in DRBD include: A lack of Primary-Secondary connectivity The Secondary operating in standalone mode Both nodes reporting connectivity but neither one in the role of master Both nodes reporting themselves in the role of master Verify the DRBD status The following command is used to verify that DRBD is operating normally on the master and slave nodes. drbd-overview When run on the master node, the output should look like the following: 1:r0/0 Connected Primary/Secondary UpToDate/UpToDate C r----- /mnt/drbd ... When run on the slave node, the output should look like the following: 1:r0/0 Connected Secondary/Primary UpToDate/UpToDate C r----- The following sections are examples of issues f

Get Docker CE for CentOS #centos #docker

Get Docker CE for CentOS Estimated reading time: 10 minutes To get started with Docker CE on CentOS, make sure you meet the prerequisites , then install Docker . Prerequisites Docker EE customers To install Docker Enterprise Edition (Docker EE), go to Get Docker EE for CentOS instead of this topic . To learn more about Docker EE, see Docker Enterprise Edition . OS requirements To install Docker CE, you need a maintained version of CentOS 7. Archived versions aren’t supported or tested. The centos-extras repository must be enabled. This repository is enabled by default, but if you have disabled it, you need to re-enable it . The overlay2 storage driver is recommended. Uninstall old versions Older versions of Docker were called docker or docker-engine . If these are installed, uninstall them, along with associated dependencies. $ sudo yum remove docker \ docker-client \ docker-client-latest \