README v8.61.2 2025-07-17
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. NED Secrets - Securing your Secrets1. General
This document describes the alu-sr 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: 7750 SROS 14.0.0 |
| | | |
| check-sync | yes | Several check-sync strategies acceped (config-hash, last-updated |
| | | timestamp etc) |
| | | |
| partial-sync-from | yes | Native device CLI commands supported (eg 'info' inside a node). |
| | | Check partial-show-method ned-settings |
| | | |
| live-status actions | yes | Commands suported as live-status exec: admin|any|debug|ping|show |
| | | |
| live-status show | yes | Supports several live-status 'show' TTL-based commands |
| | | |
| load-native-config | yes | |
+---------------------------+-----------+------------------------------------------------------------------+Custom NED Features
+---------------------------+-----------+------------------------------------------------------------------+
| Feature | Supported | Info |
+---------------------------+-----------+------------------------------------------------------------------+
| apply-device-config- | yes | Supported methods: CLI, scp-transfer, sftp-transfer |
| method | | |
| | | |
| apply-device-config- | yes | Supported methods: CLI, scp-transfer, sftp-transfer |
| method | | |
| | | |
| get-device-config-method | yes | Supported methods: CLI, scp-transfer, sftp-transfer |
| | | |
| candidate-commit | yes | Needs to be enabled on the device also |
| | | |
| number-of-lines-to-send- | yes | Configurable number of lines to be sent in one chunk |
| in-chunk | | |
| | | |
| persistent-store | yes | Configure how the NED shall save configuration to persistent |
| | | memory |
| | | |
| trans-id-method | yes | Configure how the NED shall calculate the transaction id (full |
| | | config hash, last modified date etc) |
| | | |
| ned-secrets | yes | NED supports device-enctypted password caching. Please check |
| | | README.md |
| | | |
| proxy | yes | Supports up to two proxy jumps |
| | | |
| custom-transaction-error- | yes | Supports definition of custom device errors to be thrown by the |
| definition | | NED |
| | | |
| ignore-bof-in-trans-id | yes | Configure if BOF section should be ignored or not at trans-id |
| | | computation (eg ignore BOF at check-sync) |
+---------------------------+-----------+------------------------------------------------------------------+Verified target systems
+---------------------------+-----------------+--------+---------------------------------------------------+
| Model | Version | OS | Info |
+---------------------------+-----------------+--------+---------------------------------------------------+
| ALCATEL SR 7750 | C-12.0.R8 | SROS | 7750 SROS-C-12.0.R8 |
| | | | |
| ALCATEL SR 7750 | C-14.0.R4 | SROS | 7750 SROS-C-14.0.R4 |
| | | | |
| ALCATEL SR 7750 | C-15.1.R2 | SROS | 7750 SROS-C-15.1.R2 |
| | | | |
| ALCATEL SR 7750 | C-16.0.R3 | SROS | 7750 SROS-C-16.0.R3 |
| | | | |
| ALCATEL SR 7750 | B-21.5.R2 | SROS | 7750 SROS-B-21.5.R2 |
| | | | |
| ALCATEL SR 7950 | C-19.7.R2 | SROS | 7950 SROS-C-19.7.R2 |
| | | | |
| ALCATEL SR 7250 | C-19.10.R6 | SROS | 7250 SROS-C-19.10.R6 |
| | | | |
| ALCATEL SR 7705 | B-5.0.R3 | SROS | 7705 SROS-B-5.0.R3 |
| | | | |
| ALCATEL SR 7210 | B-4.0.R6 | SROS | 7210 SROS-B-4.0.R6 |
| | | | |
| ALCATEL SR 7210 | B-3.0.R3 | SROS | 7210 SROS-B-3.0.R3 |
+---------------------------+-----------------+--------+---------------------------------------------------+1.1 Extract the NED package
It is assumed the NED package ncs-<NSO version>-alu-sr-<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-alu-sr-1.0.1.signed.bin > ./ncs-6.0-alu-sr-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-alu-sr-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-alu-sr-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:
alu-sr-<NED major digit>.<NED minor digit>:> tar xfz ncs-6.0-alu-sr-1.0.1.tar.gz > ls -d */ alu-sr-cli-1.0Install the NED into NSO, using the ncs-setup tool:
> ncs-setup --package alu-sr-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 alu-sr-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-alu-sr-1.0.1.tar.gz --dest $NSO_RUNDIR
> ncs_cli -C -u admin
admin@ncs# packages reload
reload-result {
package alu-sr-cli-1.0
result true
}Set the environment variable NED_ROOT_DIR to point at the NSO NED package:
> export NED_ROOT_DIR=$NSO_RUNDIR/packages/alu-sr-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-alu-sr-1.0.tar.gz admin@ncs# software packages list package { name ncs-6.0-alu-sr-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 alu-sr-1.0 admin@ncs# software packages list package { name ncs-6.0-alu-sr-1.0.tar.gz installed }Load the NED package
admin@ncs# packages reload admin@ncs# software packages list package { name ncs-6.0-alu-sr-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 alu-sr-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-alu-sr-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 alu-sr 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 alu-sr 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.alusr \ level level-all admin@ncs(config)# commitConfigure the NED to log to the Java logger
admin@ncs(config)# devices device dev-1 ned-settings alu-sr 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 alu-sr 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 configuring some security settings and adding them to a service vprn. First step: add CLI commands in the NED CLI:
admin@ncs(config)# devices device alu7750-5 config
admin@ncs(config-config)# system
admin@ncs(config-system)# security
admin@ncs(config-security)# pki
admin@ncs(config-pki)# ca-profile "PkiNokiaCa"
admin@ncs(config-ca-profile-PkiNokiaCa)# auto-crl-update
admin@ncs(config-auto-crl-update)# shutdown
admin@ncs(config-auto-crl-update)# exit
admin@ncs(config-ca-profile-PkiNokiaCa)# exit
admin@ncs(config-pki)# exit
admin@ncs(config-security)# exit
admin@ncs(config-system)# exit
admin@ncs(config-config)# ipsec
admin@ncs(config-ipsec)# ike-policy 2
admin@ncs(config-ike-policy-2)# auth-method cert-auth
admin@ncs(config-ike-policy-2)# dpd interval 10 max-retries 2 reply-only
admin@ncs(config-ike-policy-2)# ike-version 2
admin@ncs(config-ike-policy-2)# ipsec-lifetime 172800
admin@ncs(config-ike-policy-2)# ike-transform 1
admin@ncs(config-ike-policy-2)# exit
admin@ncs(config-ipsec)# ike-policy 3
admin@ncs(config-ike-policy-3)# auth-method cert-auth
admin@ncs(config-ike-policy-3)# dpd interval 10 max-retries 2 reply-only
admin@ncs(config-ike-policy-3)# ike-version 2
admin@ncs(config-ike-policy-3)# ipsec-lifetime 172800
admin@ncs(config-ike-policy-3)# ike-transform 1
admin@ncs(config-ike-policy-3)# exit
admin@ncs(config-ipsec)# ike-transform 1
admin@ncs(config-ike-transform-1)# isakmp-lifetime 172800
admin@ncs(config-ike-transform-1)# exit
admin@ncs(config-ipsec)# ipsec-transform 2
admin@ncs(config-ipsec-transform-2)# exit
admin@ncs(config-ipsec)# cert-profile cert-profile-1
admin@ncs(cert-profile)# entry 1
admin@ncs(config-entry-1)# cert SEGW-PKI.crt
admin@ncs(config-entry-1)# key SEGW-PKI.key
admin@ncs(config-entry-1)# exit
admin@ncs(cert-profile)# no shutdown
admin@ncs(cert-profile)# exit
admin@ncs(config-ipsec)# cert-profile cert-profile-2
admin@ncs(cert-profile)# entry 1
admin@ncs(config-entry-1)# cert SEGW-PKI.crt
admin@ncs(config-entry-1)# key SEGW-PKI.key
admin@ncs(config-entry-1)# exit
admin@ncs(cert-profile)# no shutdown
admin@ncs(cert-profile)# exit
admin@ncs(config-ipsec)# trust-anchor-profile Trust-A-Profile-1
admin@ncs(trust-anchor-profile)# trust-anchor "PkiNokiaCa"
admin@ncs(trust-anchor-profile)# exit
admin@ncs(config-ipsec)# trust-anchor-profile Trust-A-Profile-2
admin@ncs(trust-anchor-profile)# trust-anchor "PkiNokiaCa"
admin@ncs(trust-anchor-profile)# exit
admin@ncs(config-ipsec)# tunnel-template 1
admin@ncs(config-tunnel-template-1)# sp-reverse-route
admin@ncs(config-tunnel-template-1)# replay-window 128
admin@ncs(config-tunnel-template-1)# transform 2
admin@ncs(config-tunnel-template-1)# exit
admin@ncs(config-ipsec)# tunnel-template 2
admin@ncs(config-tunnel-template-2)# sp-reverse-route
admin@ncs(config-tunnel-template-2)# replay-window 128
admin@ncs(config-tunnel-template-2)# transform 2
admin@ncs(config-tunnel-template-2)# exit
admin@ncs(config-ipsec)# exit
admin@ncs(config-config)# isa
admin@ncs(config-isa)# tunnel-group 1 isa-scale-mode tunnel-limit-32k
admin@ncs(config-tunnel-group-1)# description SecGW
admin@ncs(config-tunnel-group-1)# multi-active
admin@ncs(config-tunnel-group-1)# reassembly 2000
admin@ncs(config-tunnel-group-1)# exit
admin@ncs(config-isa)# service
admin@ncs(config-service)# vprn 1234 customer 1 name 1234
admin@ncs(vprn)# interface test
admin@ncs(interface)# dynamic-tunnel-redundant-next-hop 1.1.1.1
admin@ncs(interface)# sap tunnel-1.public:2
admin@ncs(sap)# ipsec-gw Ipsecgw-1
admin@ncs(config-ipsec-gw)# shutdown
admin@ncs(config-ipsec-gw)# cert
admin@ncs(config-cert)# cert-profile cert-profile-1
admin@ncs(config-cert)# status-verify
admin@ncs(config-status-verify)# default-result good
admin@ncs(config-status-verify)# exit
admin@ncs(config-cert)# trust-anchor-profile Trust-A-Profile-2
admin@ncs(config-cert)# exit
admin@ncs(config-ipsec-gw)# default-secure-service 2000 interface private-interface-Ipsecgw-1
admin@ncs(config-ipsec-gw)# default-tunnel-template 2
admin@ncs(config-ipsec-gw)# ike-policy 3
admin@ncs(config-ipsec-gw)# local-gateway-address 1.1.1.2
admin@ncs(config-ipsec-gw)# local-id type fqdn value 1234
admin@ncs(config-ipsec-gw)# exit
admin@ncs(sap)# exit
admin@ncs(interface)# exit
admin@ncs(vprn)# exit
admin@ncs(config-service)# vprn 2000 customer 1
admin@ncs(vprn)# interface loopback_DATA_MOBILE
admin@ncs(interface)# exit
admin@ncs(vprn)# vprn 3000 customer 1
admin@ncs(vprn)# interface loopback_DATA_MOBILE
admin@ncs(interface)# exit
admin@ncs(vprn)# exit
admin@ncs(config-service)# exit
admin@ncs(config-config)# Checking the device native CLI output and then commit changes:
admin@ncs(config-service)# commit dry-run outformat native
native {
device {
name alu7750-5
data exit all
configure
ipsec
ike-policy 2 create
ike-version 2
auth-method cert-auth
dpd interval 10 max-retries 2 reply-only
exit
ike-transform 1 create
isakmp-lifetime 172800
exit
ike-policy 2 create
ike-transform 1
ipsec-lifetime 172800
exit
ike-policy 3 create
ike-version 2
auth-method cert-auth
dpd interval 10 max-retries 2 reply-only
ike-transform 1
ipsec-lifetime 172800
exit
ipsec-transform 2 create
exit
cert-profile cert-profile-1 create
entry 1 create
cert SEGW-PKI.crt
key SEGW-PKI.key
exit
no shutdown
exit
cert-profile cert-profile-2 create
entry 1 create
cert SEGW-PKI.crt
key SEGW-PKI.key
exit
no shutdown
exit
trust-anchor-profile Trust-A-Profile-1 create
exit
exit
system
security
pki
ca-profile PkiNokiaCa create
auto-crl-update create
shutdown
exit
exit
exit
exit
exit
ipsec
trust-anchor-profile Trust-A-Profile-1 create
trust-anchor PkiNokiaCa
exit
trust-anchor-profile Trust-A-Profile-2 create
trust-anchor PkiNokiaCa
exit
tunnel-template 1 create
sp-reverse-route
replay-window 128
transform 2
exit
tunnel-template 2 create
sp-reverse-route
replay-window 128
transform 2
exit
exit
isa
tunnel-group 1 isa-scale-mode tunnel-limit-32k create
description "SecGW"
multi-active
reassembly 2000
exit
exit
service
vprn 1234 customer 1 name 1234 create
interface test create
sap tunnel-1.public:2 create
ipsec-gw Ipsecgw-1
cert
cert-profile cert-profile-1
status-verify
default-result good
exit
trust-anchor-profile Trust-A-Profile-2
exit
exit
exit
exit
exit
vprn 2000 customer 1 name 2000 create
interface loopback_DATA_MOBILE create
exit
exit
vprn 1234 customer 1 name 1234 create
interface test create
sap tunnel-1.public:2 create
ipsec-gw Ipsecgw-1
default-secure-service 2000 interface private-interface-Ipsecgw-1
default-tunnel-template 2
ike-policy 3
local-gateway-address 1.1.1.2
local-id type fqdn value 1234
shutdown
exit
exit
dynamic-tunnel-redundant-next-hop 1.1.1.1
exit
exit
vprn 3000 customer 1 name 3000 create
interface loopback_DATA_MOBILE create
exit
exit
exit
exit all
}
}
admin@ncs(config-config)# commit
Commit complete.Checking if there are diffs between the device configuration and the NED CDB:
admin@ncs(config-config)# compare-config
admin@ncs(config-config)# check-sync
result in-sync
admin@ncs(config-config)#In the above commands, compare-config result should be empty and the check-sync result should be in-sync. If there are different results, it is possible that some commands failed on the device (the device output may contain errors that are not caught by the NED) or the device added some dynamic data. Trace analysis is needed in this case to understand what went wrong. If the NED missed a device error that it was supposed to be thrown by the NED, please check chapter 7 from this document and README-ned-settings.md chapter 13.1 on how to address this issue.
The commited changes can also be rolled back to the original device state, before the commit:
admin@ncs(config-config)# top rollback config
admin@ncs(config-config)# commit dry-run outformat native
native {
device {
name alu7750-5
data exit all
configure
ipsec
no ike-policy 2
exit
service
vprn 1234 customer 1 name 1234 create
interface test create
no dynamic-tunnel-redundant-next-hop
sap tunnel-1.public:2 create
ipsec-gw Ipsecgw-1
cert
no cert-profile
status-verify
no default-result
exit
no trust-anchor-profile
exit
no default-secure-service
no default-tunnel-template
no ike-policy
no local-gateway-address
no local-id
shutdown
exit
no ipsec-gw
exit
sap tunnel-1.public:2 shutdown
no sap tunnel-1.public:2
exit
exit
exit
ipsec
no ike-policy 3
no ike-transform 1
no tunnel-template 1
no tunnel-template 2
no ipsec-transform 2
cert-profile cert-profile-1 shutdown
no cert-profile cert-profile-1
cert-profile cert-profile-2 shutdown
no cert-profile cert-profile-2
no trust-anchor-profile Trust-A-Profile-1
no trust-anchor-profile Trust-A-Profile-2
exit
isa
tunnel-group 1 isa-scale-mode tunnel-limit-32k create
no description
no multi-active
no reassembly
exit
no tunnel-group 1
exit
service
vprn 1234 customer 1 name 1234 create
interface test shutdown
no interface test
exit
vprn 1234 shutdown
no vprn 1234
vprn 2000 customer 1 name 2000 create
interface loopback_DATA_MOBILE shutdown
no interface loopback_DATA_MOBILE
exit
vprn 2000 shutdown
no vprn 2000
vprn 3000 customer 1 name 3000 create
interface loopback_DATA_MOBILE shutdown
no interface loopback_DATA_MOBILE
exit
vprn 3000 shutdown
no vprn 3000
exit
system
security
pki
ca-profile PkiNokiaCa shutdown
no ca-profile PkiNokiaCa
exit
exit
exit
exit all
}
}
admin@ncs(config-config)# commit
Commit complete.
admin@ncs(config-config)# compare-config
admin@ncs(config-config)# 5. Built in live-status actions
The NED supports the following live-status exec commands:
any: Execute any command on device
ping: Send echo message
debug: Execute debug commands
show: Execute show commands
admin: Execute admin commands
any encryption re-encrypt obfuscated: this is used to force the secrets operational CDB update (please check chapter 9)
6. Built in live-status show
ALU-SR NED supports a bunch of live-status 'show' TTL-based commands. Here is a list of supported elements:
admin@ncs# show devices device alu7750-5 live-status
Possible completions:
card Display Card information
chassis Display chassis information
eth-cfm
lag
modules-state
ports Display all available ports (on all slots)
resource-usage
router Display router instance information
service Display services related information
sfm Display Switch Fabric Module (sfm) information
slot Display MDA information
system Display system params
Example of a live-status call:
admin@ncs# show devices device alu7750-5 live-status slot
live-status slot 1
mda 1
ports-maximum 20
ports-equipped 20
last-boot 2023-04-27T08:18:26-00:00
oper-state up
admin-state up
software-version "(Not Specified)"
provisioned-type m20-v
admin@ncs#
7. Limitations
Device errors: since ALU-SR is not a CISCO device, the NED does not have a complete list of device errors to be thrown.
This may lead to device errors that are missed by the NED, usually generating a compare-config issue. However, it is possible to define a custom list of device errors to be thrown by the NED. Please check the README-ned-settings.md for ned-settings alu-sr transaction config-abort-warning
YANG model: the NED behavior is not 1 to 1 with the device behavior because of the yang limitations. For this reason, there are several work-around in the NED to achieve a behavior similar to the device. For example, a leaf 'encap-type' that allows values like 'dot1q' but also allows a value like 'no encap-type' (no encap-type shown on the device), this leaf may be modeled as 'encap-type no' to also support the device 'no encap-type'.
Redeployment: a significant number of device operations requires redeployment of configuration. For instance, updates to a specific node may need to shutdown an external node first, do the update and then restore the external node state. While redeployments are common and vastly supported in ALU-SR NED, the redeployment is always done with the current NED data. For instance, the NED cannot redeploy data if the targeted data for redeployment is also changed in the current transaction.
Custom trans-id methods: using ned-settings (please check README-ned-settings.md), it is possible to change the way alu-sr NED computes trans-id. Popular choices for trans-id computation are config-hash or config-data, which basically pulls the entire device configuration in order to compute trans-id hash. These two methods are most reliable, since they catch any changes on the device, however, most of the time, device configurations are significantly large, which introduces significant get and processing time. To drastically reduce the trans-id computation time, alu-sr provides custom trans-id methods, but they have certain limitations: - rollback-timestamp: trans-id computation based on the device rollback timestamp (device rollback feature must be on). This method is unreliable because the rollback timestamp does not change when the device config is changed, only when the device is rolled back. - last-modified-timestamp: cumputes trans-id based on the device last modified timestamp. This method is reliable to detect out-of-band changes, as long as the device configuration is not saved out-of-band (eg execute 'admin save' on the device). When saving the device configuration out-of-band (eg 'admin save'), this timestamp is invalidated by the device. - last-saved-timestamp: this method uses the last saved device timestamp. This method is reliable as long as the device changes are saved every time, either from the NED or from the device. Note: out-of-band changes of the device that are not saved will not be detected by this method - last-modified-and-last-saved-timestamp: this method uses both last modified and last saved timestamps. This method is reliabe to detect both out-of-band modifications or configuration save on the device. Limitation for this method is that the NED will be in out-of-sync state when the device configuration is not modified but it is saved (eg when 'admin save' is used out-of-band, the NED will be in out-of-sync state, even though the device configuration was not actually modified)
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 alu-sr 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 alu-sr 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. 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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