Andrey Zhdanov sorquan

Pacemaker - pcs & crmsh cheatsheet

General Operations

Display the configuration

crmsh # crm configure show xml
pcs   # pcs cluster cib

To show a simplified (non-xml) syntax

crmsh # crm configure show

Veritas Volume Manager

VM daemons

Name	Description
vxconfigd It can be in three states: Enable = Normal mode Disable = Most operations cannot be be used Booted = Normal startup while using boot disk group	Maintains system configuration in the kernel & disk (private region).If the daemon is stopped it does not disable any configuration state loaded into the kernel, it only affects the ability to make configuration changes until vxconfigd is restarted.
vxrelocd	Monitors for failure events and relocates failed subdisks
vxconfigbackupd	Used to backup configuration chnages, the files created can be used with vxmake to restored lost groups.

Veritas NetBackup Cheatsheet

Master Server Daemons/Processes

Description	Name
Request daemon	bprd
Scheduler	bpsched (started with bprd)
Netbackup database manager	bpdbm (started with bpsched)
Job Monitor	bpjobd (started with bpdbm)

Format output with delimiter

ls /var/ | xargs | sed 's/ /,/g'

Add text to end of file if it not exists in the file

sed -e '/option=/{s/.*/option=value/;:a;n;:ba;q}' -e 'aoption=value' /dir/filename

Count inodes

Veritas Cluster Server Cheatsheet

LLT & GAB

VCS uses two components, LLT and GAB, to share data over the private networks among systems. These components provide the performance and reliability required by VCS.

Name	Description
LLT	LLT (Low Latency Transport) provides fast, kernel-to-kernel comms and monitors network connections. The system admin configures the LLT by creating a configuration file (llttab) that describes the systems in the cluster and private network links among them. The LLT runs in layer 2 of the network stack.
GAB	GAB (Group membership and Atomic Broadcast) provides the global message order required to maintain a synchronised state among the systems, and monitors disk comms such as that required by the VCS heartbeat utility. The system admin configures GAB driver by creating a configuration file ( gabtab).

Show top 10 largest directories

du -sg | sort -r | tail -n10

Special bash variables

Character	Definition
$*	Expands to the positional parameters, starting from one. When the expansion occurs within double quotes, it expands to a single word with the value of each parameter separated by the first character of the IFS special variable.
$@	Expands to the positional parameters, starting from one. When the expansion occurs within double quotes, each parameter expands to a separate word.
$#	Expands to the number of positional parameters in decimal.
$?	Expands to the exit status of the most recently executed foreground pipeline.
$-	A hyphen expands to the current option flags as specified upon invocation, by the set built-in command, or those set by the shell itself (such as the -i).
$$	Expands to the process ID of the shell.

Type	Tools
RDBMS	MySQL, Oracle Database, IBM DB2, PostgreSQL, Firebird
NoSQL	MongoDB, CouchDB, CouchBase, Cassandra, HBase, Redis, Riak, Neo4J
Load Balancing	Nginx, HAProxy
Web Servers	Nginx, Apache HTTP Server, Lighttpd, Apache Tomcat
Cluster Infrastructure	Keepalived, Heartbeat, Corosync, Pacemaker, IPVS
Version control	GitHub, BitBucket, GitLab
CI/CD	Jenkins, Bamboo, GitLab CI, TeamCity
Build Tools	Gradle, CMake

Level	Disks	Hot spare	Available space	Fault tolerance	Read	Write
RAID 0	from 2	-	disk size * dIsk count	-	high	high
RAID 1	2	+	disk size	1 disk	medium	medium
RAID 1E	2	-	disk size	1 disk	high	medium
RAID 5	from 3	+	disk size*(disk count-1)	1 disk	high	low
RAID 5EE	from 4	-	disk size*(disk count-2)	1 disk	high	low
RAID 6	from 4	+	disk size*(disk count-2)	2 disk	medium	low
RAID 10 (1+0)	from 4, even	+	disk size*(disk count/2)	1 disk in every RAID 1	medium	medium
RAID 50 (5+0)	from 6, even	+	disk size*(disk count-2)	1 disk in every RAID 5	high	low

	---
	- name: Install Web
	hosts: hostgroup
	become: true
	vars:
	- repo:
	Debian:
	- apt
	RedHat:
	- epel-release