Configuring the RedBoot Environment

Target Network Configuration

Each node in a networked system needs to have a unique address. Since the network support in RedBoot is based on TCP/IP, this address is an IP (Internet Protocol) address. There are two ways for a system to “know” its IP address. First, it can be stored locally on the platform. This is known as having a static IP address. Second, the system can use the network itself to discover its IP address. This is known as a dynamic IP address. RedBoot supports this dynamic IP address mode by use of the BOOTP (a subset of DHCP) protocol. In this case, RedBoot will ask the network (actually some generic server on the network) for the IP address to use.

The choice of IP address type is made via the fconfig command. Once a selection is made, it will be stored in flash memory. RedBoot only queries the flash configuration information at reset, so any changes will require restarting the platform.

Here is an example of the RedBoot fconfig command, showing network addressing:

RedBoot> fconfig -l
Run script at boot: false
Use BOOTP for network configuration: false
Local IP address: 192.168.1.29
Default server IP address: 192.168.1.101
DNS server IP address: 192.168.1.1
GDB connection port: 9000
Network debug at boot time: false  

In this case, the board has been configured with a static IP address listed as the Local IP address. The default server IP address specifies which network node to communicate with for TFTP service. This address can be overridden directly in the TFTP commands.

The DNS server IP address option controls where RedBoot should make DNS lookups. A setting of 0.0.0.0 will disable DNS lookups. The DNS server IP address can also be set at runtime.

If the selection for Use BOOTP for network configuration had been true, these IP addresses would be determined at boot time, via the BOOTP protocol. The final number which needs to be configured, regardless of IP address selection mode, is the GDB connection port. RedBoot allows for incoming commands on either the available serial ports or via the network. This port number is the TCP port that RedBoot will use to accept incoming connections.

These connections can be used for GDB sessions, but they can also be used for generic RedBoot commands. In particular, it is possible to communicate with RedBoot via the telnet protocol. For example, on Linux®:

% telnet redboot_board 9000
Connected to redboot_board
Escape character is ‘^]’.
RedBoot>  

Host Network Configuration

RedBoot may require three different classes of service from a network host:

• dynamic IP address allocation, using BOOTP

• TFTP service for file downloading

• DNS server for hostname lookups

Depending on the host system, these services may or may not be available or enabled by default. See your system documentation for more details.

In particular, on Red Hat Linux, neither of these services will be configured out of the box. The following will provide a limited explanation of how to set them up. These configuration setups must be done as root on the host or server machine.

--------------- /etc/dhcpd.conf -----------------------------
default-lease-time 600;
max-lease-time 7200;
option subnet-mask 255.255.255.0;
option broadcast-address 192.168.1.255;
option domain-name-servers 198.41.0.4, 128.9.0.107;
option domain-name “bogus.com”;
allow bootp;
shared-network BOGUS {
subnet 192.168.1.0 netmask 255.255.255.0 {
         option routers 192.168.1.101;
         range 192.168.1.1 192.168.1.254;
}
 }
host mbx {
         hardware ethernet 08:00:3E:28:79:B8;
         fixed-address 192.168.1.20;
         filename “/tftpboot/192.168.1.21/zImage”;
         default-lease-time -1;
         server-name “srvr.bugus.com”;
         server-identifier 192.168.1.101;
         option host-name “mbx”;
} 

# service dhcpd start

--------------- /etc/named.conf -----------------------------
// generated by named-bootconf.pl

options {
        directory "/var/named";
        /*
         * If there is a firewall between you and nameservers you want
         * to talk to, you might need to uncomment the query-source
         * directive below.  Previous versions of BIND always asked
         * questions using port 53, but BIND 8.1 uses an unprivileged
         * port by default.
         */
        // query-source address * port 53;


        forward first;
        forwarders {
                212.242.40.3;
                212.242.40.51;
        };
};

//
// a caching only nameserver config
//
// Uncomment the following for Red Hat Linux 7.2 or above:
// controls {
//         inet 127.0.0.1 allow { localhost; } keys { rndckey; };
// };
// include "/etc/rndc.key";
zone "." IN {
        type hint;
        file "named.ca";
};

zone "localhost" IN {
        type master;
        file "localhost.zone";
        allow-update { none; };
};

zone "0.0.127.in-addr.arpa" IN {
        type master;
        file "named.local";
        allow-update { none; };
};

# service named start

# chkconfig named on

Verification

Once your network setup has been configured, perform simple verification tests as follows:

• Reboot your system, to enable the setup, and then try to ‘ping’ the target board from a host.

• Once communication has been established, try to ping a host using the RedBoot ping command - both by IP address and hostname.

• Try using the RedBoot load command to download a file from a host.