This NED is equipped with a number of runtime configuration options "NED settings" allowing for customization by the end user. All options are configurable using the NSO API for NED settings. Most NED settings can be configured globally, per device profile or per device instance in the following locations:
global /ncs:devices/global-settings/ned-settings/overture-1400/ profile /ncs:devices/ncs:profiles/profile:/ned-settings/overture-1400/ device /ncs:/device/devices/device:/ned-settings/overture-1400/
Profiles setting overrides global-settings and device settings override profile settings, hence the narrowest scope of the setting is used by the device.
If user changes a ned-setting, then user must reconnect to the device, i.e. disconnect and connect in order for the new setting to take effect.
From the NSO CLI the device instance NED settings for this NED are available under:
Configure settings specific to the connection between NED and device.
Configure settings specific to the connection between NED and device.
Deprecated ned-settings.
Settings for controlling logs generated.
Settings used when writing to device.
List specifying tail-f actions executed from operational mode, not configuration mode.
answers to device prompting questions.
# config
# devices device dev-1 ned-settings overture-1400
Press TAB to see all the NED settings.
1. ned-settings overture-1400
2. connection
3. deprecated
4. logger
5. operational-actions
5.1. commands
6. live-status
6.1. auto-prompts- extended-parser <enum> (default auto)
Make the overture-1400 NED handle CLI parsing (i.e. transform the running-config from the
device to the model based config tree).
auto - Uses turbo-mode when available, will use fastest availablemethod to load
data to NSO. If NSO doesn't support data-loading from CLI NED, robust-mode
is used.
turbo-mode - The NED executes the whole command parsing by itself, completely bypassing
the NSO CLI parser. The configuration dump is transferred to NSO using maapi
setvalues call.
turbo-xml-mode - The NED executes the whole command parsing by itself, completely bypassing
the NSO CLI parser. The configuration dump is transferred to NSO in XML
format.
robust-mode - Makes the NED filter the configuration so that unmodeled content is removed
before being passed to the NSO CLI-engine. This protects against
configuration ending up at the wrong level when NSO CLI parser fallbacks
(which potentially can cause following config to be skipped).- connection remote-name <string>
User name on the device.
- connection ssh client <enum>
Configure the SSH client to use. Relevant only when using the NED with NSO 5.6 or later.
ganymed - The legacy SSH client. Used on all older versions of NSO.
sshj - The new SSH client with support for the latest crypto features. This is the default
when using the NED on NSO 5.6 or later.
- connection ssh host-key known-hosts-file <string>
Path to openssh formatted 'known_hosts' file containing valid host keys.
- connection ssh host-key public-key-file <string>
Path to openssh formatted public (.pub) host key file.
- connection ssh auth-key private-key-file <string>
Path to openssh formatted private key file.
- connection character-set <string> (default UTF-8)
Character set to use for telnet session.
- connection number-of-retries <uint8> (default 0)
Configure max number of retries the NED will try to connect to the device before giving up.
Default 0.
- connection time-between-retry <uint8> (default 1)
Configure the time in seconds the NED will wait between each connect retry. Default 1s.
- connection connector <WORD>
Change the default connector, e.g. 'ned-connector-default.json'.
- connection terminal width <uint32> (default 255)
- connection terminal height <uint32> (default 255)- deprecated connection legacy-mode <enum> (default disabled)
enabled - enabled.
disabled - disabled.- logger level <enum> (default debug)
Set level of logging.
error - error.
info - info.
verbose - verbose.
debug - debug.
- logger java <true|false> (default true)
Toggle logs to be added to ncs-java-vm.log.- operational-actions commands <name>
- name <WORD>
String or regular expression, e.g.: monitor interface or monitor.*.- live-status time-to-live <int32> (default 50)
Define time-to-live for data fetched from the device via live-status.(default 50).- live-status auto-prompts <id> <question> <answer>
- id <WORD>
List id, any string.
- question <WORD>
Device question, regular expression.
- answer <WORD>
Answer to device question.This document describes the overture-1400 NED.
The NED connects to the device CLI using SSH. Configuration is done by sending native CLI commands to the device through the communication channel.
Additional README files bundled with this NED package
Common NED Features
Verified target systems
It is assumed the NED package ncs-<NSO version>-overture-1400-<NED version>.signed.bin has already
been downloaded from software.cisco.com.
In this instruction the following example settings will be used:
NSO version: 6.0
NED version: 1.0.1
NED package downloaded to: /tmp/ned-package-store
Extract the NED package and verify its signature:
In case the signature can not be verified (for instance if no internet connection), do as below instead:
The result of the extraction shall be a tar.gz file with the same name as the .bin file:
There are two alternative ways to install this NED package. Which one to use depends on how NSO itself is setup.
In the instructions below the following example settings will be used:
NSO version: 6.0
NED version: 1.0.1
NED download directory: /tmp/ned-package-store
NSO run time directory: ~/nso-lab-rundir
A prerequisite is to set the environment variable NSO_RUNDIR to point at the NSO run time directory:
This section describes how to install a NED package on a locally installed NSO (see "NSO Local Install" in the NSO Installation guide).
It is assumed the NED package has been been unpacked to a tar.gz file as described in 1.1.
Untar the tar.gz file. This creates a new sub-directory named:overture-1400-<NED major digit>.<NED minor digit>:
Install the NED into NSO, using the ncs-setup tool:
Open a NSO CLI session and load the new NED package like below:
Alternatively the tar.gz file can be installed directly into NSO. Then skip steps 1 and 2 and do like below instead:
Set the environment variable NED_ROOT_DIR to point at the NSO NED package:
This section describes how to install a NED package on a system installed NSO (see "NSO System Install" in the NSO Installation Guide).
It is assumed the NED package has been been unpacked to a tar.gz file as described in 1.1.
Do a NSO backup before installing the new NED package:
Start a NSO CLI session and fetch the NED package:
Install the NED package (add the argument replace-existing if a previous version has been loaded):
Load the NED package
This section describes the steps for configuring a device instance using the newly installed NED package.
Start a NSO CLI session:
Enter configuration mode:
Configure a new authentication group (my-group) to be used for this device:
Configure a new device instance (example: dev-1):
If the sync-from was not successful, check the NED configuration again.
It is often desirable to see details from when and how the NED interacts with the device(Example: troubleshooting)
This can be achieved by configuring NSO to generate a trace file for the NED. A trace file contains information about all interactions with the device. Messages sent and received as well as debug printouts, depending on the log level configured.
NSO creates one separate trace file for each device instance with tracing enabled. Stored in the following location:
$NSO_RUNDIR/logs/ned-overture-1400-cli-1.0-<device name>.trace
Do as follows to enable tracing in one specific device instance in NSO:
Start a NSO CLI session:
Enter configuration mode:
Enable trace raw:
Alternatively, tracing can be enabled globally affecting all configured device instances:
Configure the log level for printouts to the trace file:
The log level 'info' is used by default and the 'debug' level is the most verbose.
IMPORTANT: Tracing shall be used with caution. This feature does increase the number of IPC messages sent between the NED and NSO. In some cases this can affect the performance in NSO. Hence, tracing should normally be disabled in production systems.
An alternative method for generating printouts from the NED is to enable the Java logging mechanism. This makes the NED print log messages to common NSO Java log file.
$NSO_RUNDIR/logs/ncs-java-vm.log
Do as follows to enable Java logging in the NED
Start a NSO CLI session:
Enter configuration mode:
Enable Java logging with level all from the NED package:
Configure the NED to log to the Java logger
Alternatively Java logging can be enabled globally affecting all configured device instances using this NED package.
IMPORTANT: Java logging does not use any IPC messages sent to NSO. Consequently, NSO performance is not affected. However, all log printouts from all log enabled devices are saved in one single file. This means that the usability is limited. Typically single device use cases etc.
This NED has the following host environment dependencies:
Java 1.8 (NSO version < 6.2)
Java 17 (NSO version >= 6.2)
Gnu Sed
Dependencies for NED recompile:
Apache Ant
Bash
Gnu Sort
Gnu awk
Example:
The NED has support for all Overture-1400 exec commands by use of the
devices device dev-1 live-status exec <any> action.
By default, the tail-f action commands are sent from the configuration mode.
If there are commands that must be executed from the operational mode, the user
must add the name of the command under the following ned-settings list:
devices device dev-1 ned-settings overture-1400 operational-actions commands.
Example:
"monitor interface 0.1" must be executed from the operational mode, so the user will add it as below:
The tail-f action will look like below:
Generally, the command output parsing halts when the NED detects an operational or config prompt, however sometimes the command requests additional input, 'answer(s)' to questions.
To respond to device question(s) there are 2 different methods,
checked in the listed order below:
[1] the ned-settings overture-1400 live-status auto-prompts list
[2] the command line args | prompts option
IMPORTANT:
[2] can be used to override an answer in auto-prompts.
Read on for details on each method:
[1]. ned-settings overture-1400 live-status auto-prompts list
The auto-prompts list is used to pass answers to questions, to exit parsing, reset timeout or ignore output which triggered the the built-in question handling. Each list entry contains a question (regex format) and an optional answer (text or built-in keyword).
Here are some examples of auto-prompts ned-settings:
NOTE:
Due to backwards compatibility, ned-setting "auto-prompts" questions get ".*" appended to their regex unless ending with "$".
[2]. "| prompts"
"| prompts" is passed in the command args string and is used to submit answer(s) to the device without a matching question pattern. IMPORTANT:
It can also be used to override answer(s) configured in auto-prompts list, unless the auto-prompts contains "" or "", which are always handled first.
One or more answers can be submitted following this syntax:
A general example (not applicable directly to overture):
Additional patterns triggering "| prompts" may be configured by use of auto-lists and setting the answer to "". This will force the user to specify the answer in "| prompts".
The "" or "IGNORE" keywords can be used to ignore device output matching the above and continue parsing. If all output should be ignored, i.e. for a show command, "| noprompts" should be used.
Some final notes on the "answer" leaf:
"ENTER" or "" means a carriage return + line feed is sent.
"IGNORE", "" or unset means the prompt was not a question, the device output is ignored and parsing continues.
A single letter answer is sent without carriage return + line, i.e. 'N' will be sent as 'N' only, with no return. If you want a return, set "NO" as the answer instead.
NONE
NONE
Issues like bugs and errors shall always be reported to the Cisco NSO NED team through the Cisco Support channel:
The following information is required for the Cisco NSO NED team to be able to investigate an issue:
Do as follows to gather the necessary information needed for your device, here named 'dev-1':
Enable full debug logging in the NED
Configure the NSO to generate a raw trace file from the NED
If the NED already had trace enabled, clear it in order to submit only relevant information
Do as follows for NSO 6.4 or newer:
Do as follows for older NSO versions:
Requests for new features and extensions of the NED are handled by the Cisco NSO NED team when applicable. Such requests shall also go through the Cisco support channel.
The following information is required for feature requests and extensions:
Set the config on the real device including all existing dependent config and run sync-from to show it in the trace.
Run sync-from # devices device dev-1 sync-from
Attach the raw trace to the ticket
List the config you want implemented in the same syntax as shown on the device
To rebuild the NED do as follows:
When the NED has been successfully rebuilt, it is necessary to reload the package into NSO.
This NED supports multi factor authentication (MFA) using the ssh authentication method 'keyboard-interactive'.
Some additional steps are required to enable the MFA support:
Verify that your NSO version supports MFA. This is configurable as additional settings in the authentication group used by the device instance.
Enter a NSO CLI and enter the following and do tab completion:
If 'mfa' is displayed in the output like above, NSO has MFA support enabled. In case MFA is not supported it is necessary to upgrade NSO before proceeding.
Implement the authenticator executable. The MFA feature relies on an external executable to take care of the client part of the multi factor authentication. The NED will automatically call this executable for each challenge presented by the ssh server and expects to get a proper response in return.
The executable can be a simple shell script or a program implemented in any programming language.
The required behaviour is like this:
In case of connection problems the following steps can help for debugging:
Enable the NED trace in debug level:
Try connect again
Inspect the generated trace file.
Verify that the ssh client is using the external authenticator executable:
Verify that the executable is called with the challenges presented by the ssh server:
Check for any errors reported by the NED when calling the executable
1. General
1.1 Extract the NED package
1.2 Install the NED package
1.2.1 Local install
1.2.2 System install
1.3 Configure the NED in NSO
2. Optional debug and trace setup
3. Dependencies
4. Sample device configuration
5. Built in live-status actions
6. Built in live-status show
7. Limitations
8. How to report NED issues and feature requests
9. How to rebuild a NED
10. Configure the NED to use ssh multi factor authenticationIf configured protocol is ssh, do fetch the host keys now:
Finally commit the configuration
Verify configuration, using a sync-from.
Python3 (with packages: re, sys, getopt, subprocess, argparse, os, glob)
Reproduce the found issue using ncs_cli or your NSO service. Write down each necessary step in a reproduction report.
In addition to this, it helps if you can show how it should work by manually logging into the device using SSH/TELNET and type the relevant commands showing a successful operation.
Gather the reproduction report and a copy of the raw trace file containing data recorded when the issue happened.
Contact the Cisco support and request to open a case. Provide the gathered files together with access details for a device that can be used by the Cisco NSO NED when investigating the issue.
SSH/TELNET access to a device that can be used by the Cisco NSO NED team for testing and verification of the new feature. This usually means that both read and write permissions are required. Pseudo access via tools like Webex, Zoom etc is not acceptable. However, it is ok with access through VPNs, jump servers etc as long as we can connect to the NED via SSH/TELNET.
read one line from stdin The line passed from the NED will be a semi colon separated string containing the following info:
The elements for device name, user, password and opaque corresponds to what has been configured in NSO. The ssh server name, instruction and prompt are given by the ssh server during the authentication step.
Each individual element in the semi colon separated list is Base64 encoded.
Extract the challenge based on the contents above.
Print a response matching the challenge to stdout and exit with code 0
In case a matching response can not be given do exit with code 2
Below is a simple example of an MFA authenticator implemented in Python3:
Configure the authentication group used by the device instance to enable MFA. There are two configurables available:
executable The path to the external multi factor authentication executable (mandatory).
opaque Opaque data that will passed as a cookie element to the executable (optional).
Try connecting to the device.
admin@ncs(config)# devices device dev-1 ssh fetch-host-keysadmin@ncs(config)# commitadmin@ncs(config)# devices device dev-1 sync-from
result true[<device name>;<user>;<password>;<opaque>;<ssh server name>;<ssh server instruction>;<ssh server prompt>;]> ncs_cli -C -u admin
admin@ncs# config
Entering configuration mode terminal
admin@ncs(config)# devices authgroups group <name> default-map mfa executable <path to the executable>
admin@ncs(config)# devices authgroups group <name> default-map mfa opaque <some opaque data>
admin@ncs(config)# commit+---------------------------+------------------------------------------------------------------------------+
| Name | Info |
+---------------------------+------------------------------------------------------------------------------+
| README-ned-settings.md | Information about all run time settings supported by this NED. |
+---------------------------+------------------------------------------------------------------------------++---------------------------+-----------+------------------------------------------------------------------+
| Feature | Supported | Info |
+---------------------------+-----------+------------------------------------------------------------------+
| netsim | yes | - |
| | | |
| check-sync | yes | - |
| | | |
| partial-sync-from | yes | - |
| | | |
| live-status actions | yes | - |
| | | |
| live-status show | no | - |
| | | |
| load-native-config | no | - |
+---------------------------+-----------+------------------------------------------------------------------++---------------------------+-----------------+--------+---------------------------------------------------+
| Model | Version | OS | Info |
+---------------------------+-----------------+--------+---------------------------------------------------+
| ISG-1400 | 13.1.1.31 | Maestr | - |
| | | OS | |
+---------------------------+-----------------+--------+---------------------------------------------------+> cd /tmp/ned-package-store
> chmod u+x ncs-6.0-overture-1400-1.0.1.signed.bin
> ./ncs-6.0-overture-1400-1.0.1.signed.bin> ./ncs-6.0-overture-1400-1.0.1.signed.bin --skip-verification> ls *.tar.gz
ncs-6.0-overture-1400-1.0.1.tar.gz> export NSO_RUNDIR=~/nso-lab-rundir> tar xfz ncs-6.0-overture-1400-1.0.1.tar.gz
> ls -d */
overture-1400-cli-1.0> ncs-setup --package overture-1400-cli-1.0 --dest $NSO_RUNDIR> ncs_cli -C -u admin
admin@ncs# packages reload
reload-result {
package overture-1400-cli-1.0
result true
} > ncs-setup --package ncs-6.0-overture-1400-1.0.1.tar.gz --dest $NSO_RUNDIR
> ncs_cli -C -u admin
admin@ncs# packages reload
reload-result {
package overture-1400-cli-1.0
result true
}> export NED_ROOT_DIR=$NSO_RUNDIR/packages/overture-1400-cli-1.0> $NCS_DIR/bin/ncs-backup> ncs_cli -C -u admin
admin@ncs# software packages fetch package-from-file \
/tmp/ned-package-store/ncs-6.0-overture-1400-1.0.tar.gz
admin@ncs# software packages list
package {
name ncs-6.0-overture-1400-1.0.tar.gz
installable
}admin@ncs# software packages install overture-1400-1.0
admin@ncs# software packages list
package {
name ncs-6.0-overture-1400-1.0.tar.gz
installed
}admin@ncs# packages reload
admin@ncs# software packages list
package {
name ncs-6.0-overture-1400-cli-1.0
loaded
}> ncs_cli -C -u adminadmin@ncs# configure
Entering configuration mode terminal
admin@ncs(config)#admin@ncs(config)# devices authgroup group my-group default-map remote-name <user name on device> \
remote-password <password on device>admin@ncs(config)# devices device dev-1 address <ip address to device>
admin@ncs(config)# devices device dev-1 port <port on device>
admin@ncs(config)# devices device dev-1 device-type cli ned-id overture-1400-cli-1.0
admin@ncs(config)# devices device dev-1 state admin-state unlocked
admin@ncs(config)# devices device dev-1 authgroup my-groupadmin@ncs(config)# devices device dev-1 protocol <ssh or telnet>> ncs_cli -C -u adminadmin@ncs# configure
Entering configuration mode terminal
admin@ncs(config)#admin@ncs(config)# devices device dev-1 trace raw
admin@ncs(config)# commitadmin@ncs(config)# devices global-settings trace raw
admin@ncs(config)# commitadmin@ncs(config)# devices device dev-1 ned-settings overture-1400 logger \
level [debug | verbose | info | error]
admin@ncs(config)# commit> ncs_cli -C -u adminadmin@ncs# configure
Entering configuration mode terminal
admin@ncs(config)#admin@ncs(config)# java-vm java-logging logger com.tailf.packages.ned.isg1400 \
level level-all
admin@ncs(config)# commitadmin@ncs(config)# devices device dev-1 ned-settings overture-1400 logger java true
admin@ncs(config)# commitadmin@ncs(config)# devices global-settings ned-settings overture-1400 logger java true
admin@ncs(config)# commitinterface gigabit 0.1
admin up
duplex full
name DESCRIPTION
no auto-negotiation
speed 10
back
uni uni-1 0.1
all-to-one
no bundling
no service-multiplexing
stp tunnel
back
admin@ncs(config-config)# commit dry-run outformat native
native {
device {
name a-overture
data interface gigabit 0.1
admin up
duplex full
name DESCRIPTION
no auto-negotiation
speed 10
back
!
uni uni-1 0.1
all-to-one
no bundling
no service-multiplexing
stp tunnel
back
!
}
}admin@ncs(config)# devices device dev-1 ned-settings overture-1400 operational-actions commands monitor interface
admin@ncs(config-device-dev-1)# commit
Commit complete.
admin@ncs(config-device-dev-1)# disconnect
admin@ncs(config-device-dev-1)# connectadmin@ncs(config)# devices device dev-1 live-status exec any "monitor interface 0.1"devices global-settings ned-settings overture-1400 live-status auto-prompts Q1 question "System configuration has been modified" answer "no"
devices global-settings ned-settings overture-1400 live-status auto-prompts Q2 question "Do you really want to remove these keys" answer "yes"
devices global-settings ned-settings overture-1400 live-status auto-prompts Q3 question "Press RETURN to continue" answer ENTER | prompts <answer 1> .. [answer N]devices device dev-1 live-status exec any "reload | prompts no yes"- A detailed recipe with steps to reproduce the issue.
- A raw trace file generated when the issue is reproduced.
- SSH/TELNET access to a device where the issue can be reproduced by the Cisco NSO NED team.
This typically means both read and write permissions are required.
Pseudo access via tools like Webex, Zoom etc is not acceptable.
However, it is ok with device access through VPNs, jump servers etc though.ncs_cli -C -u admin
admin@ncs# configure
admin@ncs(config)# devices device dev-1 ned-settings overture-1400 logging level debug
admin@ncs(config)# commitadmin@ncs(config)# devices device dev-1 trace raw
admin@ncs(config)# commitadmin@ncs(config)# devices device dev-1 clear-traceadmin@ncs(config)# devices clear-trace> cd $NED_ROOT_DIR/src
> make clean alladmin@ncs# packages reload> ncs_cli -C -u admin
admin@ncs# show running-config devices authgroups group default default-map <tab>
Possible completions:
action-name The action to call when a notification is received.
callback-node Invoke a standalone action to retrieve login credentials for managed devices on the 'callback-node' instance.
mfa Settings for handling multi-factor authentication towards the device
public-key Use public-key authentication
remote-name Specify device user name
remote-password Specify the remote password
remote-secondary-password Second password for configuration
same-pass Use the local NCS password as the remote password
same-secondary-password Use the local NCS password as the remote secondary password
same-user Use the local NCS user name as the remote user name> devices device dev-1 trace raw
> devices device dev-1 ned-settings overture-1400 logger level debug
> commitusing ssh external mfa executable: <configured path to executable>calling external mfa executable with ssh server given name: '<name>', instruction: '<instruction>', prompt '<challenge>'ERROR: external mfa executable failed <....>admin@ncs(config)# devices device global-settings ned-settings overture-1400 logger \
level [debug | verbose | info | error]
admin@ncs(config)# commitadmin@ncs(config)# devices device dev-1 compare-config#!/usr/bin/env python3
import sys
import base64
# This is an example on how to implement an external multi factor authentication handler
# that will be called by the NED upon a ssh 'keyboard-interactive' authentication
# The handler is reading a line from stdin with the following expected format:
# [<device name>;<user>;<password>;<opaque>;<ssh server name>;<ssh server instruction>;<ssh server prompt>;]
# All elements are base64 encoded.
def decode(arg):
return str(base64.b64decode(arg))[2:-1]
if __name__ == '__main__':
query_challenges = {
"admin@localhost's password: ":'admin',
'Enter SMS passcode:':'secretSMScode',
'Press secret key: ':'2'
}
# read line from stdin and trim brackets
line = sys.stdin.readline().strip()[1:-1]
args = line.split(';')
prompt = decode(args[6])
if prompt in query_challenges.keys():
print(query_challenges[prompt])
exit(0)
else:
exit(2)