DDevice COnfiguration Flashcards
What are the two types of configuration?
Active
Candidate
Where does a candidate config come from?
It spawns when you enter configure mode. Created based on the current running config.
How do you apply a candidate configuration?
Commit.
if it passes the syntax checks it gets moved to active.
How many rollback configs are stored?
Active + 49 old (50)
How many users can be in configure mode at the same time?
32
Whats configure exclusive?
Enters you into configuration mode and stops, and blocks other users entering it until you’re done.
Whats configure private?
Enables multi-user config with each user getting their own candidate config.
All other users must use config private
rollback 0 rolls back only that users candidate while private mode is active.
An admin can take over with configure exclusive.
What happens when two users apply the same config in configure private?
First users commit is good.
Second user will get a commit error advising over-write coming. if they commit again it will use the second users config.
what is config batch?
batch config mode. its for applying lots of small config changes in batches to be more efficient. Changes are queued up, and then the batch server applies them together.
What is configure dynamic?
Its a lightweight config mode for creating routing policies and routing objects.
Commits faster.
What does ; in the config mean?
Means the end of a leaf - nothing else in that specific context.
how do you go up in the config heirarchy?
up
or to move up x levels;
up x
How do you use top?
top takes you to the top of the hierarchy.
it can be chained with other commands to go up and then down another branch - eg;
top edit system login
what does exit do?
takes you back to the previous level hierarchy you were in
If you’re already at the top exit takes you out of config mode back to operational
exit configuration mode also quits you back to op instantly.
What does deactivate do?
Turns off a block of config without removing all of the config commands.
What does activate do?
turns a block of config back on again
command “set interface ge-0/0/0 disable” was commited. How do you undo it?
delete interfaces ge-0/0/0 disable
how do you view the candidate config?
from config mode, show
You can use more specific commands like;
show system services
how do you view the specific set commands in a config?
show system services | display set
Where can you commit from?
Any level, unless you’re in commit private - and then you have to be at the top
Commits on dual RE devices?
commit synchronize pushes the candidate to both REs
How do you config auto commit synchronize?
set system commit synchronize
what does commit check do?
syntax checks the candidate config without applying it
what does commit confirmed do?
Commits the config and starts a 10 minute timer. At the end of the timer it reverts.
end the timer and confirm the commit with a second commit.
This prevents you locking yourself out of a device.
By default its 10 minutes. You can specify between 1 and 65,535 minutes.
What does commit at <time> do?</time>
schedules a commit
View scheduled commits with
show system commit
cancel them with
clear system commit
How do you compare the candidate to the active config?
from configure mode,
show | compare
how do you know if you have a scheduled commit?
show system commit
look for “commit requested by <user> via cli at <datetime></datetime></user>
how do you add a comment to a commit?
commit comment
what does commit prepare do?
it creates a new version of the config, does syntax validation but doesnt make the config live yet.
commit activate completes the prepare.
How do you compare active to a rollback config?
show configuration | compare rollback <number></number>
how do you compare two text files?
file compare files <file1> <file2></file2></file1>
how do you change the number of rollback configs that can be saved?
edit system
set max-configurations-on-flash <1-49>
Whats the rescue config?
Allows you to define a known working config prior to making changes. Means you dont need to remember or track which rollback is good.
Can also be used as a last resort if the config/backup config gets lost.
How do you make a rescue config?
Request system configuration rescue save
how do you revert to the rescue config?
rollback rescue
commit
What is the Ephemeral configuration database?
Alternate config DB for commiting config changes.
Accessed via JET/XML API - not CLI
Fast. can do 1,000’s of commits/min.
Does only basic syntax checks. You can commit config that references things that dont exist which will break stuff.
What happens if the config databases during a commit conflict?
Ephemeral wins.
