GNU Screen cheatsheet

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Change to other region ctrl-a tab
Change to other screen ctrl-a 0-9
Detach ctrl-a d
Help ctrl-a ?
Kill screen ctrl-a \
Kill region ctrl-a x
New screen ctrl-a c
Reattach screen -r
Serial connection screen /dev/ttyUSB0 9600
Split ctrl-a s

Subversion Cheatsheet

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Add to working copy svn add
Backup to hot copy hot-backup.py /opt/svn /opt/svn-backup
Change log view svn log file:///opt/svn/scripts/firewall/firewall-new
Checkout svn checkout file:///opt/svn/profile
Commit changes svn commit --message "Your log message"
Copy to working copy svn copy
Create respository svnadmin create --fs-type fsfs /opt/svn
Delete from working copy svn delete
Diff changes svn diff
Initial Import svn import . file:///opt/svn --message "Initial import"
Merging to current directory svn merge
Move file in working copy svn move
Remote Checkout svn checkout svn+ssh://@/opt/svn/
Revert all changes svn revert
Review changes svn status
Review commit log svn log
Update working copy svn update (may overwrite changes)
View file svn cat file:///opt/svn/profile/.profile
View repository tree svnlook tree /opt/svn

Heartbeat 2 cheatsheet

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Commands

List cluster resources. crm_resource -L
Dump cluster configuration as xml to stdout. cibadmin -Q
Place node in standby (maintenance mode). Technically this is adding the standby property. crm_standby -U -v true
Place local node in standby. crm_standby -v true
Place node online or remove the standby property. crm_standby -D -U
Place local node online or remove standby property. crm_standby -D
View cluster status. One time to stdout. crm_mon -1
View cluster status. Refresh every 3s. crm_mon -i3
One line simple output. crm_mon -s
Show inactive resources. crm_mon -r
Stop resource. crm_resource -r -p target_role -v stopped
Start resource. crm_resource -r -p target_role -v started
Clear failed resource. crm_resource -C -H -r
Query running cluster for current state (STDOUT). cibadmin -Q --obj_type resources

Choosing a host naming convention

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Hello, my name is Dns

Whether realizing it or not every organization goes through the process of selecting a naming convention. Often this is done without much forward planing resulting in unwieldy host and service names. In the worst cases host names are dropped completely and either by habit or lack of a proper DNS service only ip addresses are used.

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