Setup cisco switch to download ios server

A relay device forwards broadcast traffic between two directly connected LANs. A router does not forward broadcast packets, but it forwards packets based on the destination IP address in the received packet. When you boot up your switch , the DHCP client is invoked and requests configuration information from a DHCP server when the configuration file is not present on the switch.

If the configuration file is present and the configuration includes the ip address dhcp interface configuration command on specific routed interfaces, the DHCP client is invoked and requests the IP address information for those interfaces. With this message, the client and server are bound, and the client uses configuration information received from the server.

The amount of information the switch receives depends on how you configure the DHCP server. The offer from the DHCP server is not a guarantee that the IP address is allocated to the client; however, the server usually reserves the address until the client has had a chance to formally request the address. If the switch accepts replies from a BOOTP server and configures itself, the switch broadcasts, instead of unicasts, TFTP requests to obtain the switch configuration file.

The configuration files on all clients are identical except for their DHCP-obtained hostnames. If a client has a default hostname the hostname name global configuration command is not configured or the no hostname global configuration command is entered to remove the hostname , the DHCP hostname option is not included in the packet when you enter the ip address dhcp interface configuration command.

In this case, if the client receives the DCHP hostname option from the DHCP interaction while acquiring an IP address for an interface, the client accepts the DHCP hostname option and sets the flag to show that the system now has a hostname configured. You can use the DHCP image upgrade features to configure a DHCP server to download both a new image and a new configuration file to one or more switches in a network.

Simultaneous image and configuration upgrade for all switches in the network helps ensure that each new switch added to a network receives the same image and configuration. The DHCP-based autoconfiguration with a saved configuration process stops if there is not at least one Layer 3 interface in an up state without an assigned IP address in the network.

Unless you configure a timeout, the DHCP-based autoconfiguration with a saved configuration feature tries indefinitely to download an IP address. The auto-install process stops if a configuration file cannot be downloaded or if the configuration file is corrupted.

The configuration file that is downloaded from TFTP is merged with the existing configuration in the running configuration but is not saved in the NVRAM unless you enter the write memory or copy running-configuration startup-configuration privileged EXEC command. If the downloaded configuration is saved to the startup configuration, the feature is not triggered during subsequent system restarts.

The downloaded configuration file becomes the running configuration of the switch. It does not over write the bootup configuration saved in the flash, until you reload the switch. You can use DHCP auto-image upgrade with DHCP autoconfiguration to download both a configuration and a new image to one or more switches in your network. The switch or switches downloading the new configuration and the new image can be blank or only have a default factory configuration loaded.

If the new configuration is downloaded to a switch that already has a configuration, the downloaded configuration is appended to the configuration file stored on the switch.

Any existing configuration is not overwritten by the downloaded one. After you install the switch in your network, the auto-image update feature starts. The downloaded configuration file is saved in the running configuration of the switch , and the new image is downloaded and installed on the switch. When you reboot the switch , the configuration is stored in the saved configuration on the switch. Follow these guidelines if you are configuring a device as a DHCP server:.

You should configure the DHCP server with reserved leases that are bound to each switch by the switch hardware address. Router IP address default gateway address to be used by the switch required. Boot filename the name of the configuration file that the client needs recommended. Depending on the settings of the DHCP server, the switch can receive IP address information, the configuration file, or both. If you do not configure the DHCP server with the lease options described previously, it replies to client requests with only those parameters that are configured.

If the IP address and the subnet mask are not in the reply, the switch is not configured. Unavailability of other lease options does not affect autoconfiguration. The switch can act as a DHCP server. These features are not operational. If you did not specify the configuration filename, the TFTP server, or if the configuration file could not be downloaded, the switch attempts to download a configuration file by using various combinations of filenames and TFTP server addresses.

The files include the specified configuration filename if any and these files: network-config, cisconet. For the switch to successfully download a configuration file, the TFTP server must contain one or more configuration files in its base directory. The files can include these files:. The configuration file named in the DHCP reply the actual switch configuration file. The router-confg or the ciscortr. The preferred solution is to configure the DHCP server with all the required information.

The TFTP server contains the configuration files for the switch. If it is on a different LAN, the switch must be able to access it through a router. Depending on the availability of the IP address and the configuration filename in the DHCP reserved lease, the switch obtains its configuration information in these ways:. The IP address and the configuration filename is reserved for the switch and provided in the DHCP reply one-file read method.

The switch sends a unicast message to the TFTP server to retrieve the named configuration file from the base directory of the server and upon receipt, it completes its boot up process. The switch sends a broadcast message to a TFTP server to retrieve the named configuration file from the base directory of the server, and upon receipt, it completes its boot-up process. The configuration filename is not provided two-file read method.

The switch sends a unicast message to the TFTP server to retrieve the network-confg or cisconet. If the network-confg file cannot be read, the switch reads the cisconet.

The default configuration file contains the hostnames-to-IP-address mapping for the switch. The switch fills its host table with the information in the file and obtains its hostname. If the hostname is not found in the file, the switch uses the hostname in the DHCP reply.

If the hostname is not specified in the DHCP reply, the switch uses the default Switch as its hostname. After obtaining its hostname from the default configuration file or the DHCP reply, the switch reads the configuration file that has the same name as its hostname hostname -confg or hostname. If the cisconet. If the switch cannot read the network-confg, cisconet. If the switch cannot read the router-confg file, it reads the ciscortr. With a normally operating switch , you enter the boot loader mode only through the console connection.

Unplug the switch power cord, then reconnect the power cord. Hold down the MODE button until you see the boot loader switch prompt. The switch boot loader software provides support for nonvolatile environment variables, which can be used to control how the boot loader or any other software running on the system, functions.

Environment variables that have values are stored in flash memory outside of the flash file system. Each line in these files contains an environment variable name and an equal sign followed by the value of the variable. A variable has no value if it is not present; it has a value if it is listed even if the value is a null string. Many environment variables are predefined and have default values. Data that controls code, which does not read the Cisco IOS configuration file.

For example, the name of a boot loader helper file, which extends or patches the functionality of the boot loader can be stored as an environment variable. Data that controls code, which is responsible for reading the Cisco IOS configuration file. For example, the name of the Cisco IOS configuration file can be stored as an environment variable.

You can change the settings of the environment variables by accessing the boot loader or by using Cisco IOS commands. Under normal circumstances, it is not necessary to alter the setting of the environment variables. This table describes the function of the most common environment variables. A semicolon-separated list of executable files to try to load and execute when automatically booting. If the BOOT environment variable is not set, the system attempts to load and execute the first executable image it can find by using a recursive, depth-first search through the flash file system.

If the BOOT variable is set but the specified images cannot be loaded, the system attempts to boot the first bootable file that it can find in the flash file system.

Specifies the Cisco IOS image to load during the next boot cycle on which the image is loaded. This command changes the setting of the BOOT environment variable. Valid values are 1, yes, 0, and no. If it is set to no or 0, the boot loader attempts to automatically boot up the system. If it is set to anything else, you must manually boot up the switch from the boot loader mode.

The next time you reboot the system, the switch is in boot loader mode. Changes the filename that Cisco IOS uses to read and write a nonvolatile copy of the system configuration. Specifies the filename that Cisco IOS uses to read and write a nonvolatile copy of the system configuration.

You can schedule a reload of the software image to occur on the switch at a later time for example, late at night or during the weekend when the switch is used less , or you can synchronize a reload network-wide for example, to perform a software upgrade on all switches in the network. Reload of the software to take affect in the specified minutes or hours and minutes.

The reload must take place within approximately 24 hours. You can specify the reason for the reload in a string up to characters in length. Reload of the software to take place at the specified time using a hour clock.

If you specify the month and day, the reload is scheduled to take place at the specified time and date. If you do not specify the month and day, the reload takes place at the specified time on the current day if the specified time is later than the current time or on the next day if the specified time is earlier than the current time. Specifying schedules the reload for midnight. The reload command halts the system. The console connection is made with a rolled cable usually a flat black cable , and connects the console port of the router to the COM port of the PC.

Open Hyperterminal on the PC, and use the following settings:. Ping the router access server to verify that a network connection exists between them. Step 3 Copy the new software image from the TFTP server to the router access server using the following commands:. Note Cisco recommends that you keep a copy of the router or access server configuration before upgrading the router or access server software.

Step 5 When prompted, enter the filename of the Cisco IOS software image to be installed, as in the following example:. Step 6 Specify the destination filename:. This is the name the new software image will have when it is loaded onto the router. The image can be named anything, but common practice is to enter the UNIX image filename.

Step 7 Erase the Flash device before confirming:. Enter yes to erase the existing software image resident in the router's Flash memory before copying the new one.

Enter no to keep the existing software image. Be sure that you have enough Flash memory to keep both. The copying process requires several minutes; the time differs from network to network. During the copying process, messages are displayed to indicate which files have been accessed.

The exclamation point "! Each exclamation point indicates that ten packets have been transferred successfully. A checksum verification of the image occurs after the image is written to Flash memory. Downloads the images file from the RCP server to the switch and overwrites the current image.

Downloads the images file from the RCP server to the switch and saves the current image. If there is not enough room to install the new image and keep the running image, the download process stops, and an error message is displayed. You can upload an image from the switch to an RCP server. The upload feature should be used only if the web management pages associated with Device Manager have been installed with the existing image.

Uploads the currently running switch image to the network server. Skip to content Skip to search Skip to footer. Book Contents Book Contents.

Find Matches in This Book. PDF - Complete Book 1. Updated: March 28, Chapter: Working with Image Files. These sections contain this configuration information: Note For a list of software images and the supported upgrade paths, see the release notes. File Format of Images on a Server or Cisco. Ensure that the switch has a route to the TFTP server. The switch and the TFTP server must be in the same subnetwork if you do not have a router to route traffic between subnets.

Check connectivity to the TFTP server by using the ping command. For download operations, ensure that the permissions on the file are set correctly. The permission on the file should be world-read. Before uploading the image file, you might need to create an empty file on the TFTP server.

To create an empty file, enter the touch filename command, where filename is the name of the file you will use when uploading the image to the server. During upload operations, if you are overwriting an existing file including an empty file, if you had to create one on the server, ensure that the permissions on the file are set correctly.

Permissions on the file should be world-write. Caution For the download and upload algorithms to operate properly, do not rename image names. When you copy an image file from the switch to a server by using FTP, the Cisco IOS software sends the first valid username in this list: The username specified in the archive download-sw or archive upload-sw privileged EXEC command if a username is specified.

The username set by the ip ftp username username global configuration command if the command is configured. The switch sends the first valid password in this list: The password specified in the archive download-sw or archive upload-sw privileged EXEC command if a password is specified. The password set by the ip ftp password password global configuration command if the command is configured. The switch creates a password named username switchname.

The username variable is the username associated with the current session, switchname is the configured hostname, and domain is the domain of the switch. Before you begin downloading or uploading an image file by using FTP, complete these tasks: Ensure that the switch has a route to the FTP server. The switch and the FTP server must be in the same subnetwork if you do not have a router to route traffic between subnets. Check connectivity to the FTP server by using the ping command.

If you are accessing the switch through the console or a Telnet session and you do not have a valid username, make sure that the current FTP username is the one that you want to use for the FTP download. You can enter the show users privileged EXEC command to view the valid username. If you do not want to use this username, create a new FTP username by using the ip ftp username username global configuration command. This new name will be used during all archive operations.

If you are accessing the switch through a Telnet session and you have a valid username, this username is used, and you do not need to set the FTP username.

Include the username in the archive download-sw or archive upload-sw privileged EXEC command if you want to specify a username for that operation only.

When you upload an image file to the FTP server, it must be properly configured to accept the write request from the user on the switch. Command Purpose Step 1 configure terminal Example: Switch configure terminal Optional Enters global configuration mode on the switch. When you copy an image from the switch to a server by using RCP, the Cisco IOS software sends the first valid username in this list: The username specified in the archive download-sw or archive upload-sw privileged EXEC command if a username is specified.

The username set by the ip rcmd remote-username username global configuration command if the command is entered. The remote username associated with the current TTY terminal process. For example, if the user is connected to the router through Telnet and was authenticated through the username command, the switch software sends the Telnet username as the remote username.

The switch hostname. Before you begin downloading or uploading an image file by using RCP, do these tasks: Ensure that the workstation acting as the RCP server supports the remote shell rsh. Ensure that the switch has a route to the RCP server. The switch and the server must be in the same subnetwork if you do not have a router to route traffic between subnets.

Check connectivity to the RCP server by using the ping command.