DHCP6: lastlease behavior after Confim non-response #387
Conversation
If lastlease is enabled, and dhcpcd is unable to confirm its prior lease, after timeout, don't continue to solicit. Confine lastlease behavior to only the CONFIRM state.
| dhcp6_bind(ifp, NULL, NULL); | ||
| return; |
There was a problem hiding this comment.
Why return?
We couldn't find any DHCPv6 server, so we do use the last lease, but we should retry and DISCOVER yes?
There was a problem hiding this comment.
Soliciting for a lease while using the current one could lead to problems if the DHCPv6 server has ping checking enabled, in the case where you come back up on the same network. We've seen it fail the ping check (ie, gets a response) and issue a new IP address when that happens, thinking there's an address conflict. I think making this behavior optional with the lastlease option allows everybody to choose which way they want to go, since it is kind of a couple of competing requirements we're trying to untangle here. What do you think?
| @@ -1760,8 +1760,9 @@ dhcp6_fail(struct interface *ifp, bool drop) | |||
| dhcp_unlink(ifp->ctx, state->leasefile); | |||
| dhcp6_addrequestedaddrs(ifp); | |||
| eloop_timeout_delete(ifp->ctx->eloop, NULL, ifp); | |||
| } else if (state->recv && ifp->options->options & DHCPCD_LASTLEASE) { | |||
| } else if (state->state == DH6S_CONFIRM && ifp->options->options & DHCPCD_LASTLEASE) { | |||
There was a problem hiding this comment.
Can we also allow the state DH6S_REBIND please?
IF you ask for a Prefix Delegation you REBIND, otherwise CONFIRM and ideally we want the behavior in both states.
And we should still check state->recv to ensure we ARE using the last lease in this state.
There was a problem hiding this comment.
Sure, I'm not seeing any issues with those changes in my own testing.
If lastlease is enabled, and dhcpcd is unable to confirm its prior lease, after timeout, don't continue to solicit. Confine lastlease behavior to only the CONFIRM state.
This cleans up some minor issues with the initial commit for DHCPv6 lastlease.