Configuring Junos OS on the EX9251
EX9251 Switch Default Configuration
Each EX9251 switch is programmed with a factory default configuration that contains the values set for each configuration parameter when a switch is shipped. The default configuration file sets values for system parameters such as the system log and file messages.
When you commit changes to the configuration, a new configuration file is created that becomes the active configuration. You can always revert to the factory default configuration. See Reverting to the Default Factory Configuration for the EX Series Switch.
This topic shows the factory default configuration file of an EX9251 switch:
Connecting and Configuring an EX9251 Switch (CLI Procedure)
The EX9251 switch is shipped with the Junos OS preinstalled
and ready to be configured when the switch is powered on. There are
two 16-MB internal NAND Flash memory devices located on the baseboard
for BIOS storage. You can insert the USB storage device into the USB
slot on the front panel. The switch also has two built-in M.2-based
solid-state drives (SSDs) (labeled SSD0 and SSD1). There are three copies of the software: one each
on the SSD drives and one on a USB flash drive that can be inserted
into the slot in the faceplate of the RE module.
When the switch boots, it first attempts to start the image
on the USB flash drive. If there is no USB flash drive installed or
if the attempt otherwise fails, the switch next attempts to start
the software from the SSD installed in slot SSD0, and finally from the SSD installed in slot SSD1.
You configure the switch by issuing Junos OS command-line
interface (CLI) commands, either on a console device attached to the
console (CON) port on the front panel, or over
a telnet connection to a network connected to the Ethernet management
(MGMT) port on the front panel.
Before you begin connecting and configuring an EX9251 switch, gather the following information:
Name the switch will use on the network
Domain name the switch will use
IP address and prefix length information for the Ethernet interface
IP address of a default switch
IP address of a DNS server
Password for the root user
This procedure connects the switch to the network, but does not enable it to forward traffic. For complete information about enabling the switch to forward traffic, including examples, see the Junos OS configuration guides.
To configure the software:
- Verify that the switch is powered on.
- Log in as the root user. There is no password.
- Start the CLI.root# cliroot@>
- Enter configuration mode.cli> configure[edit]root@#
- Set the root authentication password by entering either
a clear-text password, an encrypted password, or an SSH public key
string (DSA or RSA).[edit]root@# set system root-authentication plain-text-passwordNew password: passwordRetype new password: password
or
[edit]root@# set system root-authentication encrypted-password encrypted-passwordor
[edit]root@# set system root-authentication ssh-dsa public-keyor
[edit]root@# set system root-authentication ssh-rsa public-key - Configure the name of
the switch. If the name includes spaces, enclose the name in double
quotation marks (“ ”).[edit]root@# set system host-name host-name
- Create a user account.[edit]root@# set system login user user-name authentication plain-text-passwordNew password: passwordRetype new password: password
- Set the user account class to super-user.[edit]root@# set system login user user-name class super-user
- Configure the switch’s domain name.[edit]root@# set system domain-name domain-name
- Configure the IP address and prefix length for the switch’s
Ethernet interface.[edit]root@# set interfaces fxp0 unit 0 family inet address address/prefix-length
- Configure the IP address of a backup router, which is
used only while the routing protocol is not running.[edit]root@# set system backup-router address
- Configure the IP address of a DNS server.[edit]root@# set system name-server address
- (Optional) Configure the static routes to remote subnets
with access to the management port. Access to the management port
is limited to the local subnet. For more information about static
routes, see the Junos OS Administration Library.[edit]root@# set routing-options static route remote-subnet next-hop destination-IP retain no-readvertise
- Configure the telnet service at the [edit system
services] hierarchy level.[edit]root@# set system services telnet
- (Optional) Display the configuration to verify that it
is correct.[edit]root@# showsystem {host-name host-name;domain-name domain-name;root-authentication {authentication-method (password | public-key);}name-server {address;}}interfaces {fxp0 {unit 0 {family inet {address address/prefix-length;}}}}
- Commit the configuration
to activate it on the switch.[edit]root@# commit
- (Optional) Configure
additional properties by adding the necessary configuration statements.
Then commit the changes to activate them on the switch.[edit]root@switch# commit
- When you have finished configuring the switch, exit configuration
mode.[edit]root@switch# exitroot@switch>
Ensure that the removable storage media that contains a copy of Junos OS is not installed in the switch except when you want to install Junos OS from the storage media. If the storage media is installed during normal operation and if the switch is rebooted intentionally or accidentally (for example, as a result of a power outage), the configuration in the switch is deleted and the copy of the software in the storage media is installed in the switch.