[Dnsmasq-discuss] TFTP for IPv6

[Simon Kelley]

Ean Houts wrote:
> Hello - I'm attempting to use dnsmasq mainly for it's tftp server.  My 
> requirements are a multi-homed tftp server that serves both ipv4 and 
> ipv6 tftp clients.
> 
> I'm using fedora core 11, and the box as two NICs, both of which have 
> ipv4 and ipv6 addresses.  One of the NICs has multiple aliases with 
> distinct subnets (this is a test environment that needs to exercise alot 
> of different functionality).
> 
> Anyway, I have the dnsmasq tftp server running, but it won't respond to 
> any ipv6 addresses.  dnsmasq reports ipv6 support :
> Compile time options IPv6 GNU-getopt DBus no-I18N DHCP TFTP
> 
> And I've tried to enable this in the config - the uncommented settings 
> are :
> no-resolv
> no-poll
> enable-tftp
> tftp-root=/export/test_data/tftpboot
> tftp-no-blocksize
> conf-dir=/etc/dnsmasq.d
> 
> Unfortunately, tftp starts only listening for ipv4 :
> sudo lsof | grep tftp
> dnsmasq   24942    nobody    8u     IPv4           11864044       
> 0t0        UDP *:tftp
> 
> using the fedora core standard tftpd server, I have no problem 
> configuring it for ipv6.  Unfortunately, it doesn't seem to work very 
> well with multi-homed hosts :-(
> 
> Any pointers or tips would be greatly appreciated.
> thanks,

The TFTP server doesn't support IPv6 - my design criteria were to make
the simplest, smallest TFTP server needed to support netboot, and since
I'm not aware of any netboot infrastructure which runs over IPv6, I
didn't include that.

Adding IPv6 support would be fairly simple: the DNS part of dnsmasq does
do IPv6, so all the bits are already in place, there just need to be an
IPv6 socket listening as well as an IPv4 one, and a couple of address
fields in structures need to be extended to hold IPv6 addresses.

Cheers,

Simon.