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If a storage cluster node is connected to a network switch, ensure verify PortFast is configured on the switch ports leading to each node. Otherwise, the extended time delay can prevent netboot from delivering the Swarm image to a PXE-enabled node in a timely manner.
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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, use the primary and secondary DHCP servers as TFTP servers.
When setting up the DHCP servers, set the next-server parameter in each server to specify a separate IP address. When the primary or secondary DHCP server answers a DHCP query, it also handles the PXE boot.To prevent any network interruptions, ensure that verify 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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