[systemd-devel] mdns support to networkd

[Simon McVittie]

On 23/06/14 20:09, Vasiliy Tolstov wrote:
> Because now with avahi i can't
> publish additional addresses and need to patch sources to minimize
> timeout from 5000msec to 1000msec. (my hosts does  not have ptr
> records and for each ping i have 5 sec timeout =()

It sounds as though you have a misconfigured nss_mdns: you should
reconfigure nsswitch.conf to have mdns4_minimal [NOTFOUND=return], or
maybe mdns_minimal [NOTFOUND=return], but not mdns4 or mdns. New
installations of Debian's libnss-mdns do this:

    hosts:          files mdns4_minimal [NOTFOUND=return] dns

(perhaps with some extra resolvers like Lennart's "myhostname", but what
I quoted is the minimum) and that gets rid of the 5 second delay, at the
cost of not using mDNS for PTR lookups of addresses outside the
link-local 169.254.0.0/16 and fe80::/16 blocks.

I've wondered whether to implement an extended syntax for
/etc/mdns.allow so you can do something like

    # /etc/mdns.allow
    .lan.
    .lan
    .local.
    .local
    ptr 169.254.0.0/16
    ptr 192.168.0.0/24
    ptr fe80::/16

but haven't got round to it so far.

    S