Set timezone Centos

vim /etc/sysconfig/clock ZONE=”Europe/London”   ln -sf /usr/share/zoneinfo/Europe/London /etc/localtime done.. nJoy 😉  

Bash Datestamps

        Format/result         |       Command              |          Output ——————————+—————————-+—————————— YY-MM-DD_hh:mm:ss             | date +%F_%T                | $(date +%F_%T) YYMMDD_hhmmss                 | date +%Y%m%d_%H%M%S        | $(date +%Y%m%d_%H%M%S) YYMMDD_hhmmss (UTC version)   | date –utc +%Y%m%d_%H%M%SZ | $(date –utc +%Y%m%d_%H%M%SZ) YYMMDD_hhmmss (with local TZ) | date +%Y%m%d_%H%M%S%Z      | $(date +%Y%m%d_%H%M%S%Z) YYMMDDhhmmss                  | date +%Y%m%d%H%M%S         | $(date +%Y%m%d%H%M%S) YYMMDDhhmmssnnnnnnnnn         | date +%Y%m%d%H%M%S%N       | $(date…

Mounting an LVM file system

So after recovering a box which had a controller failure we needed to mount the old fs to recover some stuff. when trying to mount /dev/sdc2 we got: mount: unknown filesystem type ‘LVM2_member’ fix is easy : modprobe dm-mod vgchange -ay lvscan now yields: ACTIVE '/dev/VolGroup/lv_root' [50.00 GiB] inherit ACTIVE '/dev/VolGroup/lv_home' [178.46 GiB] inherit ACTIVE…

Backup and Restore Elastic search

While elastic search is usually run as a cluster, for the sake of this tutorial I am showing the _snapshot and _restore tools.   mkdir /mnt/backups/my_backup chmod 777 -R /mnt/backups/ Must available on all nodes. curl -XPUT 'http://localhost:9200/_snapshot/my_backup' -d '{ "type": "fs", "settings": { "location": "/mnt/backups/my_backup", "compress": true } }' [root@centos-base mnt]# curl -XGET 'http://localhost:9200/_snapshot/my_backup?pretty'…

Sending Elasticsearch to a syslog server

yum install rsyslog -y Add the following to rsyslog.conf on the client system ############ $ModLoad imfile $InputFileName /var/log/elasticsearch/elasticsearch.log $InputFileTag elasticsearch $InputFileStateFile stat-elasticsearch $InputFileSeverity Info $InputFileFacility daemon $InputRunFileMonitor #local3.* hostname:<portnumber> daemon.* @192.168.1.66:514 ############   Also if you want all logs to go through to syslog server:   *.* @192.168.1.66   at the end of the file….

fixing permission denied issue with udp 512 port graylog

use iptables to pre-route NAT the udp port :   iptables -A PREROUTING -t nat -i eth0 -p udp –dport 514 -j REDIRECT –to-port 10515   This will bypass the limit in the OS to ports < 1024 to non=root users . nJoy 😉  

Installing sample data in elastic search

After installing elastic search it is useful for testing and training to load some sample data. 1) create mapping : curl -XPUT http://localhost:9200/shakespeare -d ' { "mappings" : { "_default_" : { "properties" : { "speaker" : {"type": "string", "index" : "not_analyzed" }, "play_name" : {"type": "string", "index" : "not_analyzed" }, "line_id" : { "type"…

VMWare vSphere ESXi v5.5 Install Errors disk cannot partition

While adding a new disk to an ESX5.5. box it could not finish the partitioning stage and did not add to the Datastores. Apparently ESX does succeed to clean up the Disk from the GUI. NOTE: This procedure will destroy all data on the disk