illumos gate

instead of set:

zfs sharenfs="ro=host1,host2,...,host1024" dataset

can be used next:

/etc/netgroup:

netgroup_rohosts    (host1,,) (host2,,) ... (host1024,,)

zfs sharenfs="ro=netgroup_rohosts" dataset

There's an implementation of this in NexentaStor, in case anyone wants to upstream it.
https://github.com/Nexenta/illumos-nexenta/commit/bbd227bda98152331a777d5738104051002253b7

This would be very helpful.

Right now I have several NFS exports that go to every host in my site (home directories, etc). The list is too long to be used in a zfs -o sharenfs command. (Plus, having to reset sharenfs every time a host is added means errors are likely to be made). it would be quite useful to have netgroups deal with this. Right now the only way to do that is to run NIS which is a non-starter. Instead I have a shell script that re-exports every directory every time something changes. The resulting mix of /etc/dfs/dfstab and zfs sharenfs is fragile and non-optimal.

Ideally, I'd just export those filesystems to a netgroup (via zfs sharenfs) then just update /etc/netgroups when new hosts are added.

Imported the mentioned code into Omnios bloody and with the help of Andy Fiddaman did some cleanups.

Also did some initial testing given I have LDAP netgroups already tested the combination of local /etc/netgroup and
LDAP netgroups.

> getent netgroup test staff                                                                                                                                                                                                                                               
test \
    (,test,)
staff \
    (,mvw,) \
    (,ed,) \
    (,luc,) \
    (,smvw,)

Also tested the nsstest programs.

Testing with the newest version again with local /etc/netgroup and LDAP.

22:23 [mvw:europa][4] /build/illumos-gate > getent netgroup test                                                                                                                                                                                                                                                            
test (,test,)
22:23 [mvw:europa][5] /build/illumos-gate > getent netgroup staff                                                                                                                                                                                                                                                           
staff (,mvw,) (,ed,) (,luc,) (,smvw,)
22:23 [mvw:europa][6] /build/illumos-gate > getent netgroup staff \* mvw \*                                                                                                                                                                                                                                                 
staff                 (*,mvw,*) = 1

Things now mimic Solaris 11.4 which borrowed the ideas from Linux regarding the 4 key
getent netgroup syntax. Linux even has a typo in the man page as it lets you believe you
can use getent netgroup and then 3 keys but things only work with 4 e.g. netgroupname, host, user and domainname.

The output from getent netgroup is now analog to Linux and Solaris 11.4 the previous output was the way FreeBSD gives output.