traceroute(8) page also has good information about TTL.TTL is roughly the number of "hops" the packet is allowed to take.
man ping and search for ttl
Wild guess: a DHCP lease age is beyond the refresh time that the DHCP server gave with it?
do a traceroute -n 8.8.8.8. see where it loops
I don't see an -r option for dhclient.dhclient -r <interface> to release the current lease then
chclient <interface> to get a new lease
But as others have said do a traceroute
It's probably not a keep alive; based on the OP, after booting, the ping "times out" with a ttl error. That means the packet was going over more than 64 hops to reach 8.8.8.8 Basically going through 64 routers (or as covacat suggests, a loop is happening somewhere)If it's ip related do a regular ping or wget to keep alive.
I don't know the official way but I'm used to kill any dhclient and restart it to rule out problems with the DHCP-server immediately.Can I do anything at my end to get another lease?