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TFTP server software is available in both free and commercial packages. UNIX distributions commonly include TFTP server software with their the standard setup. For example, the tftp-hpa package for UNIX can integrate with Swarm. You can also obtain source code from the Linux Kernel Archives website located at kernel.org/pub/software/network/tftp.
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To set up the ISC DHCP daemon for redundancy, see "Failover with ISC DHCP" at madboa.com/geek/dhcp-failover.
To provide redundancy at the network booting layer, you can use your primary and secondary DHCP servers as TFTP servers.
When you set up your DHCP servers, set the next-server parameter in each server to specify their own a separate IP address. When the primary or secondary DHCP server answers a DHCP query, it will also handle the PXE boot.To prevent any network interruptions, ensure that the TFTP boot servers are located in the same broadcast domain (or VLAN) as the Swarm nodes or enable a DHCP relay server on the VLAN.
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