NX-OS Programmability Flashcards
what can be used to browse objects in NX-OS
Visore
what can be used to translate CLI commands to API calls
NX-API sandbox that can be enabled per device
what boot and provisioning techs are supported
POAP and PXE
what package mgmt tool is supported
RPM and YUM
what open interfaces are supported
bash, Broadcomm shell, Python and guest shell
how NX-OS can be extended
by using containers
what is POAP
power-on auto provisioning allows switch to upgrade without intervention by the admin
what triggers POAP
when switch boots and does not find its startup config
what POAP leverages
DHCP
what function POAP script plays
once the scrip is downloaded it install correct image and copies the running-config
pertaining to configuration mgmt, what else POAP can do
it can install Puppet and Chef agents on the switches
how to get to bash on nx-os
run bash
what Broadcomm shell is used for
hardware diagnostics
what Python calls to NX-OS CLI return
JSON
what is SMACK
it restricts third party containers accessing root privileges
what container technology can be run on NX-OS
LXC
how can you generate Python code
by using NX-API sandbox
what is NX-API CLI
REST like API, CLI available off the box, supports show commands, Linux bash and configuration
why NX-API is a great tool for beginners
it still sends CLI commands but returns structured data like JSON or XML
define the building blocks of NX-API
- HTTPS transport
- send commands are encoded in POST body
- responses are encoded in JSON-RPC, JSON or XML
- NGINX used as a server
what happens if NGINX resource usage exceeds cgroup limitations
process is stopped and restarted
how long the session authentication cookie is valid
600s i.e. 10 min
how do you enable NX-API
feature nxapi
nxapi https port 8443
nxapi sandbox
how NETCONF has been implemented on NX-OS
maps to commands and is based on XSD
which port NETCONF uses on NX-OS
22 (SSH)
what XML management tool can be used on client side
Python ncclient for instance
what XML documents must adhere to
to the scemas set by XSD (and YANG on other platforms)
xmlagent
on device XML/NETCONF server
xmlin
interative utility to obtain XML strings
how to translate show command to XML
show command | xmlin
how to see output of show command in XML
show command | xmlout
how to access NETCONF subsystem from client
ssh user@nxos -s netconf
what do you do when server send NETCONF hello
you reply with client side hello and ]]>]]>
NX-API REST is evolved from
NX-API CLI
tree structure used to store object info
Management Information Tree
NX-API REST is supported
Nexus 3k/9k starting from 7.0(3)
what are MOs
managed object is a name for an object instance
what is DN used for
to identify each MO
what if you miss attributes in REST call
API uses the default values (forgiving mode)
what is the role of DME
validates and rejects incorrect attributes
what is being atomic mean
if one configuration task is failed, API stops the task
REST methods that NX-API supports
POST, GET, DELETE
Pertaining to REST what does idempotency mean
the change is only done once, no matter how many times the call is done
what headers are used with NX-API REST
accept and content-type
what type of queries can be done on NX-API REST
query and class
where are Python scripts located on NX-OS
bootlfash:scripts
how do you execute on a script on NX-OS
using source command
how can you trigger a script daily
using a scheduler feature
