Hey, my ISP provides connectivity via PPPoE. An IPv6 prefix is handed out via DHCPv6 PD, which my OpenBSD gateway passes on to clients with the help of router advertisements using rad.
This works fine until the ISP disconnects me after 24h (force disconnect on ISP side). The gateway receives a new prefix via prefix delegation and rad advertises it in the local network. So far so good. However, as the old stale prefix is still valid according to the advertised lifetime, clients keep their stale IPv6 addresses. I have already decreased the lifetimes in rad to <24h, which mitigates the problem somewhat, but it's not perfect. For instance, some clients may receive the advertisement 1h before the disconnect but since the lifetimes are static, the client will assume a validity of ~23h (as set), although the prefix will expire in 1h. After some research I found out that other router advertisement daemons, e.g. radvd, have settings to alleviate this: - DeprecatePrefix will advertise a 0 plt and 2h vlt for the stale prefix - DecrementLifetimes decrements the lifetimes by the number of seconds since the last advertisement Is there any way to do this using rad or other tools? Best Henrik
