Getting Started

Using the StarOS Quick Setup Wizard

The Quick Setup Wizard consists of three parts:

  • Configuring a context-level security administrator and hostname

  • Configuring the Ethernet interface for out-of-band (OOB) management

  • Configuring the system for remote CLI access via Telnet, Secure Shell (SSH), or File Transfer Protocol (FTP)

The following figure and table provides a flow diagram that shows the run logic of the wizard along with additional information and notes.

Figure 1. StarOS Quick Setup Wizard Logic Diagram



Table 1 Quick Setup Wizard Logic Diagram Callout Descriptions
Item Task Description/Notes

1

Enter or exit the wizard.

Enter no at the prompt to automatically be directed to the command line interface (CLI). Proceed to Using the StarOS CLI for Initial Configuration for instructions on performing an initial system configuration with the CLI.

Enter setup at the command prompt to re-invoke the wizard.

2

For release 19.2 and higher, configure a tech-support password.

The tech-support password is used to access cli test-commands.

Configure an administrative username/password and the a hostname for the system.

The name of the default administrative user configured through the wizard is admin.

Administrative user name is an alphanumeric string of 1 through 32 characters that is case sensitive.

Administrative user password is an alphanumeric string of 1 through 63 characters that is case sensitive. For release 21.0 and later, you can enter 127 characters for the password.

Configure a valid, non-null hostname. The hostname is an alphanumeric string of 1 through 63 characters that is case sensitive.

3

Configure a single out-of-band management interface for the system.

Traffic on the management LAN is not transferred over the same media as user data and control signaling.

For security reasons, it is recommended that management functions be maintained on a separate network from user data and control signaling.

Configure an IP address, subnet mask, and gateway for the interface.

4

Enable the remote access protocol for accessing the system.

Secure Shell (SSH) uses TCP port number 22 by default, if enabled.

SSH V1 and/or V2 are supported.

For maximum security, use only SSH v2.

5

Enable file transfer protocols for copying files to/from the system.

If SSH is enabled, you can also enable SSH File Transfer Protocol (SFTP) server functionality.

Telnet uses TCP port number 23 by default, if enabled.

The File Transfer Protocol (FTP) uses TCP port number 21 by default, if enabled.

6

Review and/or modify the configuration of previous prompts.

  1. Enter the number of the prompt to be modified.

  2. Configure the parameter.

  3. Optional. Repeat step 1 and step 2 to modify additional settings.

  4. Enter "done" when you have completed all changes.

7

Review the configure script created by the wizard based on your inputs.

A sample of a created script is displayed in the example below. Variables are displayed in italics (variable).

8

Apply the configuration file to the system.

Once applied, the parameter configuration is automatically saved to the system.cfg file stored in /flash memory.

Sample Quick Setup Script

This is how the setup script appears if you run the EXEC mode setup command: 

[local]host_name# setup
1. Do you wish to continue with the Quick Setup Wizard[yes/no]: yes
2. Enable basic configuration[yes/no]: yes
3. Change chassis key value[yes/no]: yes
4. New chassis key value: chassis_key
5. Create new tech-support password[yes/no]: yes
6. New tech-support password: new_password
7. local context administrator username[admin]: context_admin_username
8. local context administrator password: context_admin_password
9. confirm local context administrator password: context_admin_password
10. hostname[asr5500]: hostname

Using the StarOS CLI for Initial Configuration

The initial configuration consists of the following:

  • Configuring a context-level security administrator and hostname

  • Configuring the Ethernet interface on the vNIC

  • Configuring the system for remote CLI access via Telnet, SSH, or FTP (secured or unsecured)

This section provides instructions for performing these tasks using the CLI.

    Step 1   Log into the Console port via the hypervisor.
    Step 2   At the CLI prompt, enter: 
    [local]host_name configure[local]host_name(config)
    Step 3   Enter the context configuration mode by entering the following command: 
    [local]host_name(config) context local[local]host_name(config-ctx)
    The local context is the system's management context. Contexts allow you to logically group services or interfaces. A single context can consist of multiple services and can be bound to multiple interfaces.
    Step 4   Enter the following command to configure a context-level security administrator for the system: 
    administrator user_name [ encrypted ] password password | [ ecs ] [ expiry-date date_time ] [ ftp ] [ li-administration ] [ nocli ] [ noecs ]      ]
    Note   

    You must configure a context-level security administrator during the initial configuration. After you complete the initial configuration process and end the CLI session, if you have not configured a security administrator, CLI access will be locked. See the Context Configuration Mode Commands chapter in the Command Line Interface Reference for complete information about this command.

    Step 5   Enter the following command at the prompt to exit the context configuration mode: 
    [local]host_name(config-ctx) exit
[local]host_name(config)
    Step 6   Enter the following command to configure a hostname by which the system will be recognized on the network: 
    [local]host_name(config) system hostname host_name
    host_name is the name by which the system will be recognized on the network. The hostname is an alphanumeric string of 1 through 63 characters that is case sensitive. The default hostname is "qvpc-si".
    Step 7   Configure the network interfaces on the vNIC as follows:
    1. Enter the context configuration mode by entering the following commands: 
      [local]host_name(config) context local
[local]host_name(config-ctx)
    2. Enter the following command to specify a name for the interface: 
      [local]host_name(config-ctx) interface interface_name
      interface_name is the name of the interface expressed as an alphanumeric string of 1 through 79 characters that is case sensitive. The following prompt appears as the system enters the Ethernet Interface Configuration mode: 
      [local]host_name(config-if-eth)
    3. Configure an IP address for the interface configured in the previous step by entering the following command: 
      { ip address | ipv6 address } ipaddress subnetmask
      Note   

      If you are executing this command to correct an address or subnet that was mis-configured with the Quick Setup Wizard, you must verify the default route and port binding configuration. Use step 11 and step 6 of this procedure. If there are issues, perform steps 7e through 7k to reconfigure the information.

    4. Enter the following command to exit the Ethernet interface configuration mode: 
      [local]host_name(config-if-eth) exit
[local]host_name(config-ctx)
    5. Configure a static route, if required, to point the system to a default gateway. Entering the following command: 
      { ip | ipv6 } route gw_address interface_name
    6. Enter the following to exit from the context configuration mode: 
      [local]host_name(config-ctx) exit
[local]host_name(config)
    7. Enter the Ethernet Port Configuration mode: 
      port ethernet slot/port
      For VPC, the slot number is always "1". The vNIC traffic ports are 10 through 21. Port 1 is the management port.
    8. Bind the port to the interface that you created in step 7b. Binding associates the port and all of its settings to the interface. Enter the following command: 
      [local]host_name(config-port-slot/port) bind interface interface_name local
[local]host_name(config-port-slot/port) no shutdown
      interface_name is the name of the interface that you configured in step 7b.
    9. Exit the Ethernet Interface Configuration mode by entering the command: 
      [local]host_name(config-port-slot/port) exit
[local]host_name(config)
      Note   

      The management port also supports VLANs. For additional information, refer to the VLANs section of the Interfaces and Ports chapter.

      Refer below for instructions on configuring the vNIC management interface with a second IP address.

    Configuring System Administrative Users

    This section describes some of the security features that allow security administrators to control user accounts.

    Limiting the Number of Concurrent CLI Sessions

    Security administrators can limit the number of concurrent interactive CLI sessions. Limiting the number of concurrent interactive sessions reduces the consumption of system-wide resources. It also prevents a user from potentially accessing sensitive user in formation which is already in use.

    Most privileged accounts do not require multiple concurrent logins.

    Important:

    Configuring the maximum number of sessions is recommended for all privileged accounts.

    Security administrators can limit the number of concurrent interactive CLI sessions with three different ways depending on the authentication method which his used for that particular user account.

    StarOS supports three login authentication methods:

    • TACACS+ Server users
    • Local-User users
    • AAA Context users

    For additional information on configuring the maximum number of sessions for TACACS+ Server users, see Operation. For additional information on configuring the maximum number of sessions for Local-User users and AAA context users, see Configuring Context-Level Administrative Users.

    Each authentication method must be configured separately because each of the three authentication methods can use the same user name.

    Automatic Logout of CLI Sessions

    Security administrators can configure an automatic logout of certain user accounts. Limiting the number of minutes that an interactive CLI session can be in use reduces the consumption of system-wide resources. It also prevents a user from potentially accessing a user account in a terminal window which is left idle. All authentication methods described in this section support both the idle session timeout technique and the absolute session timeout technique.

    Most privileged accounts do not require an indefinite login timeout limit.

    Important:

    Configuring the session timeout is strongly recommended for all privileged accounts.

    The idle timeout and session timeout fields in the show tacacs summary and show tacacs session id commands allow administrators to configure an automatic logout of certain accounts.

    Session Timeout: allows a security administrator to specify the maximum amount of minutes that a user can be logged in to a session before the session is automatically disconnected.

    Idle Timeout: allows a security administrator to specify the maximum amount of minutes that a session can remain in an idle state before the session is automatically disconnected.

    Important:

    The session timeout and idle timeout fields are not exclusive. If both are specified, then the idle timeout should always be lower than the session timeout since a lower session timeout will always be reached first.

    For additional information on configuring the maximum number of minutes that an interactive CLI session can be in use, see the idle-sessions threshold command and the clear tacacs sessions CLI command in the CLI Reference and the show tacacs summary and show tacacs session id in the Statistics and Counter Reference.

    Configuring the System for Remote Access

    Configure the system for remote access. An administrative user may access the system from a remote location over a local area network (LAN) or wide area network (WAN):

    • Telnet

    • Secure Shell (SSH)

    • File Transfer Protocol (FTP) (secured or unsecured)

    • Trivial File Transfer Protocol (TFTP)

    Important:

    If there are two simultaneous telnet sessions, and one administrator deletes the context into which the other administrator is logged, the administrator in the deleted context will not be automatically kicked into the local context. Although the deleted context will still appear in the CLI prompt, context specific commands will generate errors.

    Important:

    For maximum security, use SSH v2.

    Important:

    In release 20.0 and higher Trusted StarOS builds, FTP and telnet are not supported.

      Step 1   Enter the context configuration mode by entering the following command: 
      [local]host_name(config)# context local
[local]host_name(config-ctx)#
      Step 2   If desired, configure the system to allow Telnet access: 
      [local]host_name(config-ctx)# server telnetd

      For maximum system security, you should not enable telnet.

      Step 3   Configure the system to allow SSH access: 
      [local]host_name(config-ctx)# ssh generate key [ type { v1-rsa | v2-rsa | v2-dsa } ]

      v2-rsa is the recommended key type.

      In StarOS 19.2 and higher, the v1-rsa keyword has been removed from and the v2-dsa keyword has been concealed within the Context Configuration mode ssh generate CLI command. A keyword that was supported in a previous release may be concealed in subsequent releases. StarOS continues to parse concealed keywords in existing scripts and configuration files created in a previous release. But the concealed keyword no longer appears in the command syntax for use in new scripts or configuration files. Entering a question mark (?) will not display a concealed keyword as part of the Help text. A removed keyword generates an error message when parsed. 

      [local]host_name(config-ctx)# ssh generate key type v2-rsa
      Step 4   Configure the system to support SFTP: 
      [local]host_name(config-ctx)# server sshd
      [local]host_name(config-sshd)# subsystem sftp
      [local]host_name(config-sshd)# exit
      For additional information about SSH, see Configuring SSH Options
      Step 5   Configure the system to allow FTP access, if desired, by entering the following command: 
      [local]host_name(config-ctx)# server ftpd

      For maximum system security, you should not enable FTP. In release 20.0 and higher Trusted StarOS builds, FTP is not supported

      Step 6   Exit the configuration mode by entering the following command: 
      [local]host_name(config-ctx)# end
[local]host_name#
      Step 7   Verify the configuration by entering the following command: 
      [local]host_name# show configuration

      The CLI output should be similar to the sample output: 

      context local
   interface interface_name
      ip address ipaddress subnetmask
      exit
   subscriber default
      exit
   administrator admin_name password admin_password
   no server telnetd
   no server ftpd
   ssh generate key
   server sshd
   subsystem sftp
   exit
port ethernet 5/1
   bind interface interface_name local
   exit
port ethernet 5/1
   no shutdown
   exit
 snmp engine-id local 800007e580ed826c191ded2d3d
end
      Step 8   Verify the configuration of the IP routes by entering the following command: 
      [local]host_name# show ip route

      The CLI output should be similar to the sample output: 

      "*" indicates the Best or Used route.
 Destination         Nexthop          Protocol   Prec Cost Interface
*0.0.0.0/0           ipaddress      static     1    0    mio1
*network           0.0.0.0          connected  0    0    mio1
      Step 9   Verify the interface binding by entering the following command: 
      [local]host_name#  show ip interface name interface_name

      interface_name> is the name of the interface that was configured in step 7b.The CLI output should be similar to the sample output: 

      Intf Name:                      mio1
Intf Type:                      Broadcast
Description:
IP State:                       UP (Bound to 5/1 untagged, ifIndex 83951617)
IP Address:                     ipaddress      Subnet Mask:    subnetmask
Bcast Address:                  bcastaddress   MTU:            1500
Resoln Type:                    ARP            ARP timeout:        3600 secs
Number of Secondary Addresses:  0
      Step 10   Save your configuration as described in Verifying and Saving Your Configuration.

      Configuring the System for Remote Access

      Configure the system for remote access. An administrative user may access the instance from a remote location over the management network:

      • Telnet

      • Secure Shell (SSH)

      • File Transfer Protocol (FTP) (secured or unsecured)

      • Trivial File Transfer Protocol (TFTP)


      Note

      If there are two simultaneous telnet sessions, and one administrator deletes the context into which the other administrator is logged, the administrator in the deleted context will not be automatically kicked into the local context. Although the deleted context will still appear in the CLI prompt, context specific commands will generate errors.


      Note

      For maximum security, use SSH v2.

        Step 1   Enter the context configuration mode by entering the following command: 
        [local]cf_host_name(config) context local
[local]cf_host_name(config-ctx)
        Step 2   Configure the system to allow Telnet access, if desired: 
        [local]cf_host_name(config-ctx) server telnetd
        Step 3   Configure the system to allow SSH access, if desired: 
        [local]cf_host_name(config-ctx) ssh generate key [ type v2-rsa ]
        Note   

        v2-rsa is the recommended key type.

        Note   

        In Release 4.0 and higher, the v1-rsa keyword has been removed and the v2-dsa keyword has been concealed within the Context Configuration mode ssh generate CLI command. A keyword that was supported in a previous release may be concealed in subsequent releases. The system continues to parse concealed keywords in existing scripts and configuration files created in a previous release. But the concealed keyword no longer appears in the command syntax for use in new scripts or configuration files. Entering a question mark (?) will not display a concealed keyword as part of the Help text. A removed keyword generates an error message when parsed. 

        [local]cf_host_name(config-ctx) server sshd
[local]cf_host_name(config-sshd) subsystem sftp
[local]cf_host_name(config-sshd) exit
        Step 4   Configure the system to allow FTP access, if desired, by entering the following command: 
        [local]cf_host_name(config-ctx) server ftpd
        Step 5   Exit the configuration mode by entering the following command: 
        [local]cf_host_name(config-ctx) end
[local]cf_host_name
        Step 6   Verify the configuration by entering the following command: 
        [local]cf_host_name show configuration
        The CLI output should be similar to the sample output: 
        context local
   interface interface_name
      ip address ipaddress subnetmask
      exit
   subscriber default
      exit
   administrator admin_name password admin_password
   server telnetd
   server ftpd
   ssh generate key
   server sshd
   subsystem sftp
   exit
port ethernet 1/1
   bind interface interface_name local
   exit
port ethernet 1/1
   no shutdown
   exit
 snmp engine-id local 800007e580ed826c191ded2d3d
end
        Step 7   Verify the configuration of the IP routes by entering the following command: 
        [local]cf_host_name show ip route
        The CLI output should be similar to the sample output: 
        "*" indicates the Best or Used route.
 Destination         Nexthop         Protocol  Prec Cost Interface
*0.0.0.0/0           ipaddress      static     1    0    vnic1
*network            0.0.0.0         connected  0    0    vnic1
        Step 8   Verify the interface binding by entering the following command: 
        [local]cf_host_name show ip interface name interface_name
        interface_name is the name of the interface that was configured in step 7b.The CLI output should be similar to the sample output: 
        Intf Name:       vnic1

Description:
IP State:        UP (Bound to 1/1 untagged, ifIndex 83951617)
IP Address:      ipaddress          Subnet Mask:     subnetmask
Bcast Address:   bcastaddress       MTU:             1500
Resoln Type:     ARP                ARP timeout:     3600 secsL3 monitor LC-port
switchover: DiasabledNumber of Secondary Addresses:  0
        Step 9   Save your configuration as described in the Verifying and Saving Your Configuration chapter.

        Configuring SSH Options

        SSHv2 RSA is the only version of SSH supported under StarOS. Keywords previously supported for SSHv1 RSA and SSHv2 DSA have been removed from or concealed within the StarOS CLI.

        Important:

        A keyword that was supported in a previous release may be concealed in subsequent releases. StarOS continues to parse concealed keywords in existing scripts and configuration files created in a previous release. But the concealed keyword no longer appears in the command syntax for use in new scripts or configuration files. Entering a question mark (?) will not display a concealed keyword as part of the Help text. Removed keywords generate an error message when parsed.

        Version 1 of the SSH protocol is now obsolete due to security vulnerabilities. The v1-rsa keyword has been removed for the Context Configuration mode ssh command. Running a script or configuration that uses the SSHv1-RSA key returns an error message and generates an event log. The output of the error message is shown below: 

        CLI print failure Failure: SSH V1 contains multiple structural vulnerabilities and is no longer considered secure. Therefore we don't support v1-rsa SSH key any longer, please generate a new v2-rsa key to replace this old one.

        If the system boots from a configuration that contains the v1-rsa key, you can expect a boot failure when logging in through SSH. The workaround is to log in via the Console port, re-generate a new ssh v2-rsa key, and configure server sshd. It will then be possible to log in via ssh.

        The v2-dsa keyword is now concealed for the Context Configuration mode ssh command

        The v1-rsa keyword has been removed from the Exec mode show ssh key CLI command.

        SSH Host Keys

        SSH key-based authentication uses two keys, one "public" key that anyone is allowed to see, and another "private" key that only the owner is allowed to see. You create a key pair, securely store the private key on the device you want to log in from, and store the public key on the system (VPC-SI) that you wish to log into.

        SSH host keys are generated within a specified StarOS context. The context is associated with a user interface.

        You set or remove an administrative user name having authorized keys for access to the sshd server associated with context.

        Setting SSH Key Size

        The Global Configuration mode ssh key-size CLI command configures the key size for SSH key generation for all contexts (RSA host key only).

          Step 1   Enter the Global Configuration mode. 
          [local]host_name# configure
[local]host_name(config)#
          Step 2   Specify the bit size for SSH keys. 
          [local]host_name(config)# ssh key-size { 2048 | 3072 | 4096 | 5120 | 6144 | 7168 | 9216 }
          The default bit size for SSH keys is 2048 bits.

          Configuring SSH Key Generation Wait Time

          SSH keys can only be generated after a configurable time interval has expired since the last key generation. The ssh key-gen wait-time command specifies this wait time in seconds. The default interval is 300 seconds (5 minutes).

            Step 1   Enter the context configuration mode. 
            [local]host_name(config)# context context_name
            [local]host_name(config-ctx)#
            Step 2   Specify the wait time interval. 
            [local]host_name(config-ctx)# ssh key-gen wait-time seconds
            [local]host_name(config-ctx)#

            Notes:

            • seconds is specified as an integer from 0 through 86400. Default = 300

            Specifying SSH Encryption Ciphers

            The SSH Configuration mode ciphers CLI command configures the cipher priority list in sshd for SSH symmetric encryption. It changes the cipher options for that context.

              Step 1   Enter the SSH Configuration mode. 
              [local]host_name(config-ctx)# server sshd
              Step 2   Specify the desired encryption algorithms. 
              [local]host_name(config-sshd)# ciphers algorithms
              Notes:
              • algorithms is a string of 1 through 511 alphanumeric characters that specifies the algorithm(s) to be used as a single string of comma-separated variables (no spaces) in priority order (left to right) from those shown below:
                • blowfish-cbc – symmetric-key block cipher, Cipher Block Chaining, (CBC)
                • 3des-cbc – Triple Data Encryption Standard, CBC
                • aes128-cbc – Advanced Encryption Standard (AES), 128-bit key size, CBC
                • aes128-ctr – AES, 128-bit key size, Counter-mode encryption (CTR)
                • aes192-ctr – AES, 192-bit key size, CTR
                • aes256-ctr – AES, 256-bit key size, CTR
                • aes128-gcm@openssh.com – AES, 128-bit key size, Galois Counter Mode [GCM], OpenSSH
                • aes256-gcm@openssh.com – AES, 256-bit key size, GCM, OpenSSH
                • chacha20-poly1305@openssh.com – ChaCha20 symmetric cipher, Poly1305 cryptographic Message Authentication Code [MAC], OpenSSH

              The default string for algorithms in a Normal build is: 

              blowfish-cbc,3des-cbc,aes128-cbc,aes128-ctr,aes192-ctr,aes256-ctr,aes128-gcm@openssh.com,aes256-gcm@openssh.com,
chacha20-poly1305@openssh.com

              The default string for algorithms in a Trusted build is: 

              aes256-ctr,aes192-ctr,aes128-ctr
              Step 3   Exit the SSH Configuration mode. 
              [local]host_name(config-sshd)# end
[local]host_name#

              Generating SSH Keys

              The ssh generate command generates a public/private key pair which is to be used by the SSH server. The v1-rsa keyword has been removed from and the v2-dsa keyword concealed within the ssh generate CLI command. The only keyword available for generating SSH keys is v2-rsa.

              Important:

              The generated key pair remains in use until the command is issued again.

                Step 1   Enter the context configuration mode: 
                [local]host_name(config)# context context_name
                [local]host_name(config-ctx)#
                Step 2   Generate an SSH key pair. 
                [local]host_name(config-ctx)# ssh generate key type v2-rsa
                [local]host_name(config-ctx)#

                Setting SSH Key Pair

                The ssh key command sets the public/private key pair to be used by the system. The v2-dsa keyword is concealed in the ssh key command.

                Specify the SSH key pair parameters. 
                [local]host_name(config-ctx)# ssh key data length octets type v2-rsa
                Notes:
                • data is the encrypted key expressed as an alphanumeric string of 1 through 1023 characters
                • length octets is the length of the encrypted key in octets expressed as an integer from 0 through 65535
                • type specifies the key type; v2-rsa is the only supported type.
                Important:

                For releases prior to 20.0, StarOS supports a maximum of 64 configurable authorized SSH keys. For release 20.0 and higher, StarOS supports a maximum of 200 configurable authorized SSH keys.


                Authorized SSH User Access

                You must authorize users to access a StarOS context from a specific host with an SSH authentication-key pair.

                Authorizing SSH User Access

                The SSH Configuration mode authorized-key command grants user access to a context from a specified host.

                  Step 1   Go to the SSH Configuration mode. 
                  [local]host_name(config-ctx)# server sshd
                  [local]host_name(config-sshd)#
                  Step 2   Specify administrative user access via the authorized-key command. 
                  [local]host_name(config-sshd)# authorized-key username user_name host host_ip [ type { v2-dsa | v2-rsa } ]
                  Notes:
                  • username user_name specifies an existing StarOS administrator user name as having authorized keys for access to the sshd server. The user_name is expressed as an alphanumeric string of 1 through 255 characters. User names should have been previously created via the Context Configuration mode administrator command using the nopassword option to prevent bypassing of the sshd keys. Refer to the System Settings chapter for additional information on creating administrators.
                  • host host_ip specifies the IP address of an SSH host having the authorization keys for this username. The IP address must be in IPv4 dotted-decimal or IPv6 colon-separated-hexadecimal notation.
                  • type specifies the key type; v2-rsa is the only supported type.

                  SSH User Login Restrictions

                  An administrator can restrict SSH access to the StarOS CLI to a "white list" of allowed users. Access to a service may be restricted to only those users having a legitimate need. Only explicitly allowed users will be able connect to a host via SSH. The user name may optionally include a specific source IP address.

                  The AllowUsers list consists of user name patterns, separated by space. If the pattern takes the form 'USER' then login is restricted for that user. If pattern is in the format 'USER@IP_ADDRESS' then USER and IP address are separately checked, restricting logins to those users from the specified IP address.

                  The default is to allow unrestricted access by any user.

                  Creating an Allowed Users List

                  The allowusers add command allows an administrator to create a list of users who may log into the StarOS CLI.

                    Step 1   Enter the context configuration mode. 
                    [local]host_name(config)# context context_name
                    [local]host_name(config-ctx)#
                    Step 2   Go to the SSH Configuration mode. 
                    [local]host_name(config-ctx)# server sshd
                    Step 3   Configure the SSH user list. 
                    [local]host_name(config-sshd)# allowusers add user_list

                    user_list specifies a list of user name patterns, separated by spaces, as an alphanumeric string of 1 through 999 characters. If the pattern takes the form 'USER' then login is restricted for that user.

                    If the pattern is in the format 'USER@IP_ADDRESS' then user name and IP address are separately checked, restricting logins to those users from that particular IP address.

                    If the pattern is in the format 'USER@<context>@IP_ADDRESS' then user name, StarOS context and IP address are separately checked, restricting logins to those users associated with the specific context from that particular IP address.

                    The following limits apply to the user_list:

                    • The maximum length of this string is 3000 bytes including spaces.

                    • The maximum number of AllowUsers, which is counted by spaces, is 256, which is consistent with the limit from OpenSSH.

                    Important:

                    If you exceed either of the above limits, an error message is displayed. The message prompts you to use a regular expression pattern to shorten the string, or remove all the allowusers with no allowusers add or default allowusers add and re-configure.

                    For additional information, see the SSH Configuration Mode Commands chapter in the Command Line Interface Reference.

                    Step 4   Exit the SSH Configuration mode. 
                    [local]host_name(config-sshd)# end
                    [local]host_name#

                    SSH User Login Authentication

                    StarOS authenticates SSH user login attempts via authorized-key/user-account pairings for the following scenarios:

                    • User tries to login with local context username through local context (VPN) interface with authorized-key configured on local context.

                    • User tries to login with non-local context username through non-local context interface with authorized-key configured on non-local context.

                    • User tries to login with local context username through non-local context interface with authorized-key configured on local context.

                    • User tries to login with non-local context username through local context interface with authorized-key configured on non-local context.

                    A failure to authenticate based on the current system configuration prevents the login and generates an error message.

                    StarOS does not permit users with different user IDs but having the same public SSH key to login to an unauthorized context. Authentication of the user takes into account the authorized-key/user-account pairing.

                    Important:

                    For StarOS release 21.0 onwards, a user cannot access the /flash directory if the user logs in from a non-local context.

                    Secure Session Logout

                    When StarOS is disconnected from an SSH client, the default behavior has sshd terminate the CLI or SFTP session in about 45 seconds (using default parameters). Two SSH Configuration mode CLI commands allow you to disable or modify this default sshd disconnect behavior.

                    Important:

                    For higher security, Cisco recommends at least a client-alive-countmax of 2 and client-alive-interval of 5. Smaller session logout values may lead to occasional ssh session logouts. Adjust values to balance security and user friendliness.

                    The client-active-countmax command sets the number of client-alive messages which may be sent without sshd receiving any messages back from the SSH client (default =3). If this threshold is reached while the client-alive messages are being sent, sshd disconnects the SSH client thus terminating the session.

                    The client-alive-interval command sets a timeout interval in seconds (default = 15) after which if no data has been received from the SSH client, sshd sends a message through the encrypted channel to request a response from the client. The number of times that the message is sent is determined by the client-alive-countmax parameter. The approximate amount of time before sshd disconnects an SSH client disconnect = client-alive-countmax X client-alive-interval.

                    The client-alive mechanism is valuable when the client or server depend on knowing when a connection has become inactive.

                    Important:

                    The client-alive messages are sent through the encrypted channel and, therefore, are not spoofable.

                    Important:

                    These parameter apply to SSH protocol version 2 only.

                    Changing Default sshd Secure Session Logout Parameters

                    The following command sequence modifies the default settings for the ClientAliveCountmax (default = 3) and ClientAliveInterval (default = 15 seconds) parameters.
                      Step 1   Enter the context configuration mode. 
                      [local]host_name# configure
                      Step 2   Go to the SSH Configuration mode. 
                      [local]host_name(config)# context context_name
                      Step 3   Set the ClientAliveCountmax parameter to 2. 
                      [local]host_name(config-sshd)# client-alive-countmax 2
                      Step 4   Set the ClientAliveInterval parameter to 5 seconds. 
                      [local]host_name(config-sshd)# client-alive-interval 5
                      Step 5   Exit the SSH Configuration mode. 
                      [local]host_name(config-sshd)# end
[local]host_name#

                      SSH Client Login to External Servers

                      StarOS supports public key authentication for SSH/SFTP access from the StarOS gateway to external servers. You configure this feature by generating SSH client key pairs and pushing the client public key to external servers


                      Note

                      By default StarOS only supports username-password authentication to external servers.

                      Setting SSH Client Ciphers

                      The SSH Client Configuration mode ciphers CLI command configures the cipher priority list when logging into an external server.

                        Step 1   Enter the SSH Client Configuration mode. 
                        [local]host_name(config)# client ssh
                        Step 2   Specify the desired encryption algorithms. 
                        [local]host_name(config-ssh)# ciphers algorithms
                        Notes:
                        • algorithms is a string of 1 through 511 alphanumeric characters that specifies the algorithm(s) to be used as a single string of comma-separated variables (no spaces) in priority order (left to right) from those shown below:
                          • blowfish-cbc – symmetric-key block cipher, Cipher Block Chaining, (CBC)
                          • 3des-cbc – Triple Data Encryption Standard, CBC
                          • aes128-cbc – Advanced Encryption Standard (AES), 128-bit key size, CBC
                          • aes128-ctr – AES, 128-bit key size, Counter-mode encryption (CTR)
                          • aes192-ctr – AES, 192-bit key size, CTR
                          • aes256-ctr – AES, 256-bit key size, CTR
                          • aes128-gcm@openssh.com – AES, 128-bit key size, Galois Counter Mode [GCM], OpenSSH
                          • aes256-gcm@openssh.com – AES, 256-bit key size, GCM, OpenSSH
                          • chacha20-poly1305@openssh.com – ChaCha20 symmetric cipher, Poly1305 cryptographic Message Authentication Code [MAC], OpenSSH

                        The default string for algorithms in a Normal build is: 

                        aes256-ctr,aes192-ctr,aes128-ctr,aes256-gcm@openssh.com,aes128-gcm@openssh.com,chacha20-poly1305@openssh.com,
blowfish-cbc,3des-cbc,aes128-cbc

                        The default string for algorithms in a Trusted build is: 

                        aes256-ctr,aes192-ctr,aes128-ctr
                        Step 3   Exit the SSH Client Configuration mode. 
                        [local]host_name(config-ssh)# end
[local]host_name#

                        Setting Preferred Authentication Methods

                        The SSH Client Configuration mode preferredauthentications CLI command configures the preferred methods of authentication.

                          Step 1   Enter the SSH Client Configuration mode. 
                          [local]host_name(config)# client ssh
                          Step 2   Specify the preferred authentication methods. 
                          [local]host_name(config-ssh)# preferredauthentications methods
                          Notes:
                          • methods – specifies the preferred methods of authentication to be used as a single string of comma-separated variables (no spaces) in priority order (left to right) from those shown below:

                            • publickey – authentication via SSH v2-RSA protocol.

                            • keyboard-interactive – request for an arbitrary number of pieces of information. For each piece of information the server sends the label of the prompt.

                            • password – simple request for a single password

                          • default – resets the value of methods to: publickey,password

                          Step 3   Exit the SSH Client Configuration mode. 
                          [local]host_name(config-ssh)# exit
[local]host_name(config)#

                          Generating SSH Client Key Pair

                          You use commands in the SSH Client Configuration mode to specify a private key and generate the SSH client key pair.

                            Step 1   Enter the SSH client configuration mode. 
                            [local]host_name(config)# client ssh
                            [local]host_name(config-ssh)#
                            Step 2   Enter SSH private key information and key type. 
                            [local]host_name(config-ssh)# ssh key private_key_string length key_length [ type v2-rsa ]
                            [local]host_name(config-ssh)#

                            key private_key_string specifies a private key value as an alphanumeric string of 1 through 4499 characters.

                            length key_length specifies the length of the key in bytes as an integer from 0 through 65535.

                            type v2-rsa specifies the SSH client key type. The only supported SSH client key type is v2-rsa.

                            Step 3   Generate SSH client key pair. 
                            [local]host_name(config-ssh)# ssh generate key [ type v2-rsa ]
                            [local]host_name(config-ssh)#

                            type v2-rsa specifies the SSH client key type. The only supported SSH client key type is v2-rsa.

                            Step 4   Verify that the SSH client key has been generated. 
                            [local]host_name(config-ssh)# do show ssh client key
                            Step 5   Exit the SSH Client Configuration mode. 
                            [local]host_name(config-ssh)# exit
                            [local]host_name(config)#

                            Pushing an SSH Client Public Key to an External Server

                            You must push the SSH client public key to an external server to support SSH/SFTP access to that server.

                              Step 1   From the Exec mode run the push ssh-key command. 
                              [local]host_name# push ssh-key { host_name | host_ip_address } user username [ context context_name ]
                              [local]host_name#

                              host_name specifies the remote server using its logical host name which must be resolved via DNS lookup. It is expressed as an alphanumeric string of 1 to 127 characters.

                              host_ip_address is expressed in IPv4 dotted-decimal or IPv6 colon-separated-hexadecimal notation.

                              user username specifies a valid username on the external server as an alphanumeric string of 1 to 79 characters.

                              context context_name specifies a valid context name. The context name is optional. If it is not provided the current context is used for processing.

                              Step 2   Repeat Step 1 to support SSH/SFTP access on other external servers.
                              Step 3   Test SSH client login to an external server. 
                              local]host_name# ssh { hostname | ip_address } user username port port_number

                              Enabling NETCONF

                              An SSH key is a requirement before NETCONF protocol and the ConfD engine can be enabled in support of Cisco Network Service Orchestrator (NSO).

                              Refer to the NETCONF and ConfD appendix in this guide for detailed information on how to enable NETCONF.

                              Configuring the Management Interface with a Second IP Address

                              If necessary, you can configure a second IP address on the vNIC management interface.

                                 Command or ActionPurpose
                                Step 1Enter the configuration mode by entering the following command at the prompt:  
                                [local]host_name configure
[local]host_name(config)
                                 
                                Step 2Enter the following to enter the context configuration mode:  
                                [local]host_name(config) context local
[local]host-name(config-ctx)
                                 
                                Step 3Enter the interface slot number and port number via the following command:  
                                [local]host_name(config-ctx) 1/1
[local]host_name(config-if-eth)
                                 
                                Step 4Enter the secondary IP address and subnet mask by entering the following command:  
                                [local]host_name(config-if-eth) { ip | ipv } address ipaddress subnet_mask secondary
                                 
                                Step 5Exit the configuration mode by entering the following command:  
                                [local]host_name(config-if-eth) end
                                 
                                Step 6Confirm the interface ip addresses by entering the following command:  
                                [local]host_name show config context local
                                The CLI output should look similar to this example:
                                config
   context local
      interface interface_name
         ip address ipaddress subnetmask
         ip address ipaddress subnetmask secondary
         exit
                                 
                                Step 7Continue with Verifying and Saving Your Interface and Port Configuration.