Increase ilab network mtu from 1400 to 1500
Increase ilab network mtu from 1400 to 1500

We were having issues with the dell supplied PXE rom not handling
fragmented packets correctly. The TFTP packets were being fragment
and as a result the system would not boot.

We have established that an MTU of 1500 does not result in fragmentation
to both internal and external hosts:

    [centos@delete-me atftp-0.7.1]$ sudo ip l set dev em1 mtu 1500
    [centos@delete-me atftp-0.7.1]$ ping 10.60.253.241 -c1 -M do -s 1472
    PING 10.60.253.241 (10.60.253.241) 1472(1500) bytes of data.
    1480 bytes from 10.60.253.241: icmp_seq=1 ttl=64 time=0.158 ms

    --- 10.60.253.241 ping statistics ---
    1 packets transmitted, 1 received, 0% packet loss, time 0ms
    rtt min/avg/max/mdev = 0.158/0.158/0.158/0.000 ms

external:

    [centos@delete-me atftp-0.7.1]$ ping 8.8.8.8 -c1 -M do -s 1472
    PING 8.8.8.8 (8.8.8.8) 1472(1500) bytes of data.
    1480 bytes from 8.8.8.8: icmp_seq=1 ttl=55 time=6.43 ms

    --- 8.8.8.8 ping statistics ---
    1 packets transmitted, 1 received, 0% packet loss, time 0ms
    rtt min/avg/max/mdev = 6.436/6.436/6.436/0.000 ms

SKA-ScienceDataProcessor/alaska-kayobe-config