Red Bear OS
c015a375b1
mtu: per-interface MTU configuration via netcfg
LinkDevice trait gains set_mtu(mtu) with default no-op.
EthernetLink stores mtu in field, clamped to 576-9000 (RFC 791 min/max).
netcfg/ifaces/eth0/mtu becomes rw:
cat /scheme/netcfg/ifaces/eth0/mtu → '1500' (default)
echo 1400 > .../mtu → VPN MTU
echo 9000 > .../mtu → jumbo frames
Clamped to [576, 9000]:
- 576: minimum for IPv4 (RFC 791)
- 9000: standard jumbo frame MTU
Useful for VPNs (MTU 1400 to avoid fragmentation through tunnel overhead),
jumbo frames (MTU 9000 on datacenter networks), and constrained paths.