[rt27912]
Add code to suppor on {commit expiry release} statements for DHCPv6.
There are several pieces to this change
1) Add space in the iasubopt structure to hold the statement pointers
2) Update the execute code to fill in the structures as necessary
3) Execute the statements when appropriate
Many of the changes in the non-v6 code are to pass the v6 structures
around to the execute code.
[ISC-Bugs #20418] - Some systems don't support the "%s" argument to
strftime, paste together the same string using mktime instead.
[ISC-Bugs #19596] - When parsing iaid values accept printable
characters.
[ISC-Bugs #21585] - Always print time values in omshell as hex
instead of ascii if the values happen to be printable characters.
which permits a DHCP server operating in communications-interrupted state
to 'rewind' a lease to the state most recently transmitted to its peer,
greatly increasing a server's endurance in communications-interrupted.
This is supported using a new 'rewind state' record on the dhcpd.leases
entry for each lease. [ISC-Bugs #19601]
released in bursts after single fsync() events when the upper limit is
reached or if the receiving sockets go dry. The practical upshot is
that fsync-coupled server performance is now multiplicitively increased.
The default delayed ack limit is 28. Thanks entirely to a patch from
Christof Chen.
follow the leases through their lifecycles. This enables DDNS teardowns
on leases that are assigned and expired inbetween a server restart (the
state is recovered from dhcpd.leases). Arbitrary user-specified binding
scopes ('set var = "value";') are not yet supported.
3.1.0a1's tables resulted in a reduction in default server memory use.
The new selected values provide more of a zero sum (increasing the size
of tables likely to be populated, decreasing the size of tables unlikely).
- Lease structures appear in three spearate hashes: by IP address, by UID,
and by hardware address. One type of table was used for all three, and
improvements to IP address hashing were applied to all three (so UID and
hardware addresses were treated like 4-byte integers). There are now two
types of tables, and the uid/hw hashes use functions more appropriate
to their needs.
- The max-lease-misbalance percentage no longer causes scheduled rebalance
runs to be skipped: it still governs the schedule, but every scheduled
run will attempt balance.
[ISC-Bugs #16396]
