README v3.24.3 2025-06-27
Table of contents
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 authentication
11. Aflex scripts
12. NED Secrets - Securing your Secrets1. General
This document describes the a10-acos NED.
Additional README files bundled with this NED package
+---------------------------+------------------------------------------------------------------------------+
| Name | Info |
+---------------------------+------------------------------------------------------------------------------+
| README-ned-settings.md | Information about all run time settings supported by this NED. |
+---------------------------+------------------------------------------------------------------------------+Common NED Features
+---------------------------+-----------+------------------------------------------------------------------+
| Feature | Supported | Info |
+---------------------------+-----------+------------------------------------------------------------------+
| netsim | yes | Default emulated device: AX Series Advanced Traffic Manager |
| | | v2.6.1-GR1 |
| | | |
| check-sync | yes | check-sing using trans-id |
| | | |
| partial-sync-from | yes | This feature is supported by filtering the needed config from a |
| | | full show (device does not support partial show) |
| | | |
| live-status actions | yes | Supports most of the device needed actions |
| | | |
| live-status show | no | The NED does not implement TTL-based data |
| | | |
| load-native-config | no | |
+---------------------------+-----------+------------------------------------------------------------------+Custom NED Features
+---------------------------+-----------+------------------------------------------------------------------+
| Feature | Supported | Info |
+---------------------------+-----------+------------------------------------------------------------------+
| device partitions | yes | The NED supports device partitions by using config active- |
| | | partition list |
| | | |
| ned-secrets | yes | NED supports device-enctypted password caching. Please check |
| | | README.md |
+---------------------------+-----------+------------------------------------------------------------------+Verified target systems
+---------------------------+-----------------+--------+---------------------------------------------------+
| Model | Version | OS | Info |
+---------------------------+-----------------+--------+---------------------------------------------------+
| Thunder Series TH3030S | 2.7.1-GR1 | ACOS | Hardware device |
| (th3030s-1) | | | |
| | | | |
| Thunder Series TH3030S | 2.7.2-P7-SP3 | ACOS | Hardware device |
| (th3030s-2) | | | |
| | | | |
| Thunder Series Unified | 5.2.0 | ACOS | Virtual device |
| Application Service | | | |
| Gateway vThunder | | | |
| (vThunder-1) | | | |
| | | | |
| Thunder Series Unified | 5.2.0 | ACOS | Virtual device |
| Application Service | | | |
| Gateway vThunder | | | |
| (vThunder-2) | | | |
| | | | |
| Thunder Series Unified | 2.7.2-P4-SP1 | ACOS | Virtual device |
| Application Service | | | |
| Gateway vThunder | | | |
| (vThunder-27) | | | |
| | | | |
| AX Series Advanced | 2.7.2-P10 | ACOS | Virtual device |
| Traffic Manager vThunder | | | |
| (vThunder-7) | | | |
| | | | |
| Thunder Series Unified | 4.1.4-GR1-P1 | ACOS | Virtual device |
| Application Service | | | |
| Gateway vThunder | | | |
| (vThunder-8) | | | |
+---------------------------+-----------------+--------+---------------------------------------------------+1.1 Extract the NED package
It is assumed the NED package ncs-<NSO version>-a10-acos-<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:
> cd /tmp/ned-package-store > chmod u+x ncs-6.0-a10-acos-1.0.1.signed.bin > ./ncs-6.0-a10-acos-1.0.1.signed.binIn case the signature can not be verified (for instance if no internet connection), do as below instead:
> ./ncs-6.0-a10-acos-1.0.1.signed.bin --skip-verificationThe result of the extraction shall be a tar.gz file with the same name as the .bin file:
> ls *.tar.gz ncs-6.0-a10-acos-1.0.1.tar.gz
1.2 Install the NED package
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:
> export NSO_RUNDIR=~/nso-lab-rundir1.2.1 Local install
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:
a10-acos-<NED major digit>.<NED minor digit>:> tar xfz ncs-6.0-a10-acos-1.0.1.tar.gz > ls -d */ a10-acos-cli-1.0Install the NED into NSO, using the ncs-setup tool:
> ncs-setup --package a10-acos-cli-1.0 --dest $NSO_RUNDIROpen a NSO CLI session and load the new NED package like below:
> ncs_cli -C -u admin admin@ncs# packages reload reload-result { package a10-acos-cli-1.0 result true }
Alternatively the tar.gz file can be installed directly into NSO. Then skip steps 1 and 2 and do like below instead:
> ncs-setup --package ncs-6.0-a10-acos-1.0.1.tar.gz --dest $NSO_RUNDIR
> ncs_cli -C -u admin
admin@ncs# packages reload
reload-result {
package a10-acos-cli-1.0
result true
}Set the environment variable NED_ROOT_DIR to point at the NSO NED package:
> export NED_ROOT_DIR=$NSO_RUNDIR/packages/a10-acos-cli-1.01.2.2 System install
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:
> $NCS_DIR/bin/ncs-backupStart a NSO CLI session and fetch the NED package:
> ncs_cli -C -u admin admin@ncs# software packages fetch package-from-file \ /tmp/ned-package-store/ncs-6.0-a10-acos-1.0.tar.gz admin@ncs# software packages list package { name ncs-6.0-a10-acos-1.0.tar.gz installable }Install the NED package (add the argument replace-existing if a previous version has been loaded):
admin@ncs# software packages install a10-acos-1.0 admin@ncs# software packages list package { name ncs-6.0-a10-acos-1.0.tar.gz installed }Load the NED package
admin@ncs# packages reload admin@ncs# software packages list package { name ncs-6.0-a10-acos-cli-1.0 loaded }
1.3 Configure the NED in NSO
This section describes the steps for configuring a device instance using the newly installed NED package.
Start a NSO CLI session:
> ncs_cli -C -u adminEnter configuration mode:
admin@ncs# configure Entering configuration mode terminal admin@ncs(config)#Configure a new authentication group (my-group) to be used for this device:
admin@ncs(config)# devices authgroup group my-group default-map remote-name <user name on device> \ remote-password <password on device>Configure a new device instance (example: dev-1):
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 a10-acos-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>If configured protocol is ssh, do fetch the host keys now:
admin@ncs(config)# devices device dev-1 ssh fetch-host-keysFinally commit the configuration
admin@ncs(config)# commitVerify configuration, using a sync-from.
admin@ncs(config)# devices device dev-1 sync-from result true
If the sync-from was not successful, check the NED configuration again.
2. Optional debug and trace setup
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-a10-acos-cli-1.0-<device name>.trace
Do as follows to enable tracing in one specific device instance in NSO:
Start a NSO CLI session:
> ncs_cli -C -u adminEnter configuration mode:
admin@ncs# configure Entering configuration mode terminal admin@ncs(config)#Enable trace raw:
admin@ncs(config)# devices device dev-1 trace raw admin@ncs(config)# commitAlternatively, tracing can be enabled globally affecting all configured device instances:
admin@ncs(config)# devices global-settings trace raw admin@ncs(config)# commitConfigure the log level for printouts to the trace file:
admin@ncs(config)# devices device dev-1 ned-settings a10-acos logger \ level [debug | verbose | info | error] admin@ncs(config)# commitAlternatively the log level can be set globally affecting all configured device instances using this NED package.
admin@ncs(config)# devices device global-settings ned-settings a10-acos logger \ level [debug | verbose | info | error] admin@ncs(config)# commit
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:
> ncs_cli -C -u adminEnter configuration mode:
admin@ncs# configure Entering configuration mode terminal admin@ncs(config)#Enable Java logging with level all from the NED package:
admin@ncs(config)# java-vm java-logging logger com.tailf.packages.ned.a10 \ level level-all admin@ncs(config)# commitConfigure the NED to log to the Java logger
admin@ncs(config)# devices device dev-1 ned-settings a10-acos logger java true admin@ncs(config)# commitAlternatively Java logging can be enabled globally affecting all configured device instances using this NED package.
admin@ncs(config)# devices global-settings ned-settings a10-acos logger java true admin@ncs(config)# commit
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.
3. Dependencies
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
Grep
Python3 (with packages: re, sys, getopt, subprocess, argparse, os, glob)
4. Sample device configuration
The following is an example of configuration data (CLI NED commands) that can be sent to an a10-acos device:
system resource-usage class-list-ipv6-addr-count 600000
system per-vlan-limit mcast 10000
system per-vlan-limit unknown-ucast 10000
snmp-server enable traps slb application-buffer-limit
snmp-server enable traps slb server-conn-limit
snmp-server enable traps slb server-conn-resume
snmp-server enable traps slb server-down
snmp-server enable traps slb server-up
snmp-server enable traps slb service-conn-limit
snmp-server enable traps slb service-conn-resume
snmp-server enable traps slb service-down
snmp-server enable traps slb service-up
snmp-server enable traps slb vip-connlimit
snmp-server enable traps slb vip-connratelimit
snmp-server enable traps slb vip-port-connlimit
snmp-server enable traps slb vip-port-connratelimit
snmp-server enable traps slb vip-port-down
snmp-server enable traps slb vip-port-up
snmp-server enable traps system control-cpu-high
snmp-server enable traps system fan
snmp-server enable traps system high-disk-use
snmp-server enable traps system high-memory-use
snmp-server enable traps system high-temp
snmp-server enable traps system pri-disk
snmp-server enable traps system sec-disk
snmp-server enable traps system shutdown
snmp-server enable traps system start
snmp-server enable traps vrrp-a active
snmp-server enable traps vrrp-a standby
access-list 100 permit ip any any
interface ethernet 1
l3-vlan-fwd-disable
load-interval 200
enable
icmp-rate-limit 1000 lockup 2000 200
access-list 100 in
ip cache-spoofing-port
ip helper-address 2.2.2.1
ip helper-address 2.2.3.1
ip nat inside
ip nat outside
ip router isis ASD
ipv6 address fe01::/64 anycast
ipv6 address fe02::/64 anycast
ipv6 nat inside
ipv6 nat outside
interface ethernet 2
icmp-rate-limit 1000
slb server SERVER-COVERAGE-1 1.1.1.1
slb server SERVER-COVERAGE-2 2.1.1.1
slb service-group SERV-GROUP-COVERAGE-1 tcp
slb service-group SERV-GROUP-COVERAGE-2 tcp
slb service-group SERV-GROUP-COVERAGE-3 tcp
slb service-group SERV-GROUP-COVERAGE-4 tcp
slb service-group SERV-GROUP-COVERAGE-5 tcp
slb service-group SERV-GROUP-COVERAGE-6 tcp
slb service-group SERV-GROUP-COVERAGE-7 tcp
slb service-group SERV-GROUP-COVERAGE-8 tcp
slb service-group SERV-GROUP-COVERAGE-9 tcp
slb service-group SERV-GROUP-COVERAGE-10 tcp
slb service-group SERV-GROUP-COVERAGE-11 tcp
slb service-group SERV-GROUP-COVERAGE-12 tcp
slb service-group SERV-GROUP-COVERAGE-13 tcp
slb service-group SERV-GROUP-COVERAGE-14 tcp
slb service-group SERV-GROUP-COVERAGE-15 tcp
slb service-group SERV-GROUP-COVERAGE-16 tcp
slb service-group SERV-GROUP-COVERAGE-17 tcp
slb template persist cookie SLB-PERSIST-COOKIE-1
slb template persist cookie SLB-PERSIST-COOKIE-2
slb template persist cookie SLB-PERSIST-COOKIE-3
slb template persist source-ip SLB-PERSIST-SRCIP-1
slb template persist source-ip SLB-PERSIST-SRCIP-2
slb template persist source-ip SLB-PERSIST-SRCIP-3
slb template persist source-ip SLB-PERSIST-SRCIP-4
slb template persist source-ip SLB-PERSIST-SRCIP-5
slb template port SLB-TMP-PORT-1
slb template port SLB-TMP-PORT-2
slb template port SLB-TMP-PORT-3
slb template port SLB-TMP-PORT-4
slb virtual-server SLB-VIRT-SERVER-COVERAGE-1 5.1.1.1
slb virtual-server SLB-VIRT-SERVER-COVERAGE-2 5.2.1.1
slb virtual-server SLB-VIRT-SERVER-COVERAGE-3 5.3.1.1 /24
slb virtual-server SLB-VIRT-SERVER-COVERAGE-4 5.4.1.1
slb virtual-server SLB-VIRT-SERVER-COVERAGE-5 5.5.1.1
health monitor COVERAGE-HEALTH-1
retry 5
up-retry 5
override-ipv4 1.2.3.5
override-ipv6 fe01::1
override-port 1000
method https expect ASDASD
health monitor COVERAGE-HEALTH-2
method https expect response-code 100
health monitor COVERAGE-HEALTH-3
method tcp port 1 send ASDASD response contains ASDASD5. Built in live-status actions
There are two main categories of commands that can be sent using a10-acos NED: configuration commands (RPC's that are sent from the device configuration) and privileged commands (RPC's that are sent from privileged mode).
Following RPC's exemplify the two categories:
top devices device a10-0 config config-actions action { action-payload "show running-config" }
top devices device a10-0 live-status exec nonconfig-actions action { action-payload "show interface" }Each main RPC category also divides in the following sub-categories: simple commands that does not use additional prompts (eg "show configuration"), interactive commands that uses additional prompts (eg a RPC's that requests username/password or any other prompts) and internal NED commands, that does not interact with the device but with the NED.
The last category is supported but not implemented for a specific feature. Simple command format is as follows:
action { action-payload "RPC CLI command" }Interactive command contains the simple command and adds the following list:
action { action-payload "import bw-list bl1 use-mgmt-port scp://11.11.11.11/file" interaction { prompt-pattern "User name.*" value myuser } interaction { prompt-pattern Password.* value mypassword } interaction { prompt-pattern "Do you want to overwrite.*" value yes } interaction { prompt-pattern \"Do you want to save the remote host information.*\" value no } }In the above command, the interaction list defines each prompt that it is expected from the device, along with its corresponding value. Note that prompt-pattern is compiled in a regular expression, so special characters that are expected from prompts should be escaped. The order of the interaction list definition is not important, but all the possible expected prompts should be defined. For example, in the above command, the prompt "Do you want to overwrite.*" is only active when the file exists.
Internal commands looks the same as simple commands, but also contain the keyword "internal":
action { action-payload "Internal RPC" internal }All the above command sub-categories can be chained and sent in the same request, by defining a list of actions:
top devices device a10-0 live-status exec nonconfig-actions action { action-payload "show route" } action { action-payload "show interfaces" } action { action-payload "Internal RPC" internal }The new implementation of RPC action execution allows a more structured way of sending multiple RPC's, by using its XML format:
<?xml version="1.0" encoding="UTF-8"?><fragment xmlns="http://www.tailf.com">
<a10-acos-stats:action xmlns:a10-acos-stats="http://tail-f.com/ned/a10-acos-stats">
<a10-acos-stats:action-payload>import bw-list bl1 use-mgmt-port scp://11.11.11.11/file</a10-acos-stats:action-payload>
<a10-acos-stats:interaction>
<a10-acos-stats:prompt-pattern>User name.*</a10-acos-stats:prompt-pattern>
<a10-acos-stats:value>admin</a10-acos-stats:value>
</a10-acos-stats:interaction>
<a10-acos-stats:interaction>
<a10-acos-stats:prompt-pattern>Password.*</a10-acos-stats:prompt-pattern>
<a10-acos-stats:value>admin</a10-acos-stats:value>
</a10-acos-stats:interaction>
<a10-acos-stats:interaction>
<a10-acos-stats:prompt-pattern>Do you want to overwrite.*</a10-acos-stats:prompt-pattern>
<a10-acos-stats:value>yes</a10-acos-stats:value>
</a10-acos-stats:interaction>
<a10-acos-stats:interaction>
<a10-acos-stats:prompt-pattern>Do you want to save the remote host information.*</a10-acos-stats:prompt-pattern>
<a10-acos-stats:value>no</a10-acos-stats:value>
</a10-acos-stats:interaction>
</a10-acos-stats:action>
<a10-acos-stats:action xmlns:a10-acos-stats="http://tail-f.com/ned/a10-acos-stats">
<a10-acos-stats:action-payload>show running</a10-acos-stats:action-payload>
</a10-acos-stats:action>
</fragment>6. Built in live-status show
The NED does not support TTL-based live-status data
7. Limitations
The NED CLI does not implement the device behavior 1 to 1, since the device is not a netconf-compatible device. Also, the NED may use yang model workarounds (like node alternative naming) in order to support device behavior.
8. How to report NED issues and feature requests
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:
- 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.Do as follows to gather the necessary information needed for your device, here named 'dev-1':
Enable full debug logging in the NED
ncs_cli -C -u admin admin@ncs# configure admin@ncs(config)# devices device dev-1 ned-settings a10-acos logging level debug admin@ncs(config)# commitConfigure the NSO to generate a raw trace file from the NED
admin@ncs(config)# devices device dev-1 trace raw admin@ncs(config)# commitIf the NED already had trace enabled, clear it in order to submit only relevant information
Do as follows for NSO 6.4 or newer:
admin@ncs(config)# devices device dev-1 clear-traceDo as follows for older NSO versions:
admin@ncs(config)# devices clear-traceRun a compare-config to populate the trace with initial device config
admin@ncs(config)# devices device dev-1 compare-configReproduce 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.
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
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.
9. How to rebuild a NED
To rebuild the NED do as follows:
> cd $NED_ROOT_DIR/src
> make clean allWhen the NED has been successfully rebuilt, it is necessary to reload the package into NSO.
admin@ncs# packages reload10. Configure the NED to use ssh multi factor authentication
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:
> 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 nameIf '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:
read one line from stdin The line passed from the NED will be a semi colon separated string containing the following info:
[<device name>;<user>;<password>;<opaque>;<ssh server name>;<ssh server instruction>;<ssh server prompt>;]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:
#!/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)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).
> 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)# commitTry connecting to the device.
10.1 Trouble shooting
In case of connection problems the following steps can help for debugging:
Enable the NED trace in debug level:
> devices device dev-1 trace raw
> devices device dev-1 ned-settings a10-acos logger level debug
> commitTry connect again
Inspect the generated trace file.
Verify that the ssh client is using the external authenticator executable:
using ssh external mfa executable: <configured path to executable>Verify that the executable is called with the challenges presented by the ssh server:
calling external mfa executable with ssh server given name: '<name>', instruction: '<instruction>', prompt '<challenge>'Check for any errors reported by the NED when calling the executable
ERROR: external mfa executable failed <....>11. Aflex scripts
In order to activate aflex scripts support, run the following command:
admin@ncs(config-config)# config-actions action { action-payload "running-config display aflex" }Note: after running this command, it is mandatory to do a sync-from, since the device will introduce the aflex section in the running-config
Once the aflex is activated, aflex scripts can be managed. Note: since the device aflex scripts are multi-liners, the script payload needs to be properly escaped by replacing newlines - eg '\n' character with '\n'. Also double quote - eg " needs to be escaped: '"' -> '"' Also, every script should end in a '\n' Note2: since aflex script is a type string leaf in the NED, the script content needs to be quoted:
admin@ncs(config-config)# aflex test2
admin@ncs(config-aflex-test2)# script "script-content\n"For example, to create a new script that would look like this on the device:
vThunder(NOLICENSE)#show aflex test4
Name: test4
Syntax: Check
Virtual port: No
Content:
when HTTP_RESPONSE {
# Check Content-Data to avoid unnecessary collects
if { [HTTP::header "Content-Type"] contains "text" } {
HTTP::collect
}
}the equivalent config on the NED will look like this:
admin@ncs(config-config)# aflex test2
admin@ncs(config-aflex-test2)# script "when HTTP_RESPONSE {\n # Check Content-Data to avoid unnecessary collects\n if { [HTTP::header \"Content-Type\"] contains \"text\" } {\n HTTP::collect\n }\n}\n"
admin@ncs(config-aflex-test2)# commit dry-run outformat native
native {
device {
name vThunder-8
data aflex create test2
when HTTP_RESPONSE {
# Check Content-Data to avoid unnecessary collects
if { [HTTP::header "Content-Type"] contains "text" } {
HTTP::collect
}
}
.
}Disabling aflex support is done by the following command:
admin@ncs(config-config)# config-actions action { action-payload "no running-config display aflex" }12. NED Secrets - Securing your Secrets
It is best practice to avoid storing your secrets (e.g. passwords and
shared keys) in plain-text, either on NSO or on the device. In NSO we
support multiple encrypted datatypes that are encrypted using a local
key, similarly many devices such as ALU-SR supports automatically
encrypting all passwords stored on the device.
Naturally, for security reasons, NSO in general has no way of
encrypting/decrypting passwords with the secret key on the
device. This means that if nothing is done about this we will
become out of sync once we write secrets to the device.
In order to avoid becoming out of sync the NED reads back these elements
immediately after set and stores the encrypted value(s) in a special
`secrets` table in oper data. Later on, when config is read from the
device, the NED replaces all cached encrypted values with their plaintext
values; effectively avoiding all config diffs in this area. If the values
are changed on the device, the new encrypted value will not match the
cached pair and no replacement will take place. This is desired, since out
of band changes should be detected.
This handles the device-side encryption, but passwords are still unencrypted
in NSO. To deal with this we support using NSO-encrypted strings instead of
plaintext passwords in the NSO data model.
--- Handling auto-encryption
Let us say that we have password-encryption on and we want to write a new
user to our device:
system
security
user admin
access console
console
member administrative
exit
password <admin-password>
this will be automatically encrypted by the device
*A:VSR-7750>config# system security user "admin"
*A:VSR-7750>config>system>security>user# info
----------------------------------------------
password "$2y$10$fBSDYG2MHpdpCTDQhq7BE.ojwFR5z10g61PUqWaXb52GXg0Ge8d8W"
access console
console
member "administrative"
exit
----------------------------------------------
But the secrets management will store this new encrypted value in our `secrets` table:
admin@ncs# show devices device dev-1 ned-settings secrets
ID ENCRYPTED REGEX
---------------------------------------------------------------------------------------------------------------
/system/security/user_admin_/password/id $2y$10$fBSDYG2MHpdpCTDQhq7BE.ojwFR5z10g61PUqWaXb52GXg0Ge8d8W -
which means that compare-config or sync-from will not show any
changes and will not result in any updates to CDB". In fact, we can
still see the unencrypted value in the device tree:
admin@ncs(config-config)# show full sys sec user
devices device dev-1
config
system
security
user admin
access console
console
member administrative
!
password <admin-password>
--- Increasing security with NSO-side encryption
We have two alternatives, either we can manually encrypt our values using
one of the NSO-encrypted types (e.g `aes-256-cfb-128-encrypted-string`) and
set them to the tree, or we can recompile the NED to always encrypt secrets.
--- Setting encrypted value
Let us say we know that the NSO-encrypted string
`$2y$10$7ova9fF/bRe9B9GUtjVpA.w5mfeXJXRHyV0KsSfg4XWE9j3Fcq3Qi`, we
can then set it in the device tree as normal
admin@ncs(config-config)# system security user admin password $2y$10$7ova9fF/bRe9B9GUtjVpA.w5mfeXJXRHyV0KsSfg4XWE9j3Fcq3Qi
admin@ncs(config-config)# commit
when commiting this value it will be decrypted and the plaintext will be written to the device.
Unlike the previous example the plaintext is not visible in the device tree:
admin@ncs(config-config)# show full sys sec user
devices device dev-1
config
system
security
user admin
access console
console
member administrative
!
password $2y$10$7ova9fF/bRe9B9GUtjVpA.w5mfeXJXRHyV0KsSfg4XWE9j3Fcq3Qi
On the device side this plaintext value is of course encrypted
with the device key, and just as before we store it in our
`secrets` table:
admin@ncs# show devices device dev-1 ned-settings secrets
ID ENCRYPTED REGEX
---------------------------------------------------------------------------------------------------------------
/system/security/user_admin_/password/id $2y$10$fBSDYG2MHpdpCTDQhq7BE.ojwFR5z10g61PUqWaXb52GXg0Ge8d8W -
We can see that this corresponds to the value set on the device.
--- Auto-encrypting passwords in NSO
To avoid having to pre-encrypt your passwords you can rebuild your NED in your OS
command shell specifying an encrypted type for secrets using a command like:
yourhost:~/ned-folder$ NEDCOM_SECRET_TYPE="tailf:aes-cfb-128-encrypted-string" make -C src/ clean all
Or by adding the line `NED_EXTRA_BUILDFLAGS ?= NEDCOM_SECRET_TYPE=tailf:aes-cfb-128-encrypted-string`
in top of the `Makefile` located in <alu-sr-folder>/src directory.
Doing this means that even if the input to a password is a plaintext string, NSO will always
encrypt it, and you will never see plain text secrets in the device tree.
If we reload our example with the new NED all of the secrets are now encrypted:
admin@ncs(config-config)# show full sys sec user
devices device dev-1
config
system
security
user admin
access console
console
member administrative
!
password $2y$10$7ova9fF/bRe9B9GUtjVpA.w5mfeXJXRHyV0KsSfg4XWE9j3Fcq3QiLast updated
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