Got several lines of red messages like this one on the seed node. And then it crashed.
2896541ms th_a fork_database.cpp:51 push_block ] Pushing block to fork database that failed to link: 000163c506a2394a3bff81ef8bb132aca3208a3a, 91077
2896541ms th_a fork_database.cpp:52 push_block ] Head: 91387, 000164fbf83d3e90b2bb69c05e38d31c9ffd42c2
2896544ms th_a application.cpp:477 handle_block ] Error when pushing block:
3080000 unlinkable_block_exception: unlinkable block
block does not link to known chain
{}
th_a fork_database.cpp:72 _push_block
{"new_block":{"previous":"000163c4d902d1b8f9922112b51fda3aa97342e4","timestamp":"2015-10-16T20:17:03","witness":"1.6.45","transaction_merkle_root":"0000000000000000000000000000000000000000","extensions":[],"witness_signature":"1f6b7201f5ec0d128842872188c1d624d96af34a05a75445f145a973c9c25f79cf4fc3993a967ffb905f18e00edd8a3d2db1fbd29fa38ed532297530d66f722cf5","transactions":[]}}
th_a db_block.cpp:191 _push_block
witness_node: /home/emski/bitshares2/bitshares-2/libraries/net/node.cpp:1605: void graphene::net::detail::node_impl::schedule_peer_for_deletion(const peer_connection_ptr&): Assertion `_closing_connections.find(peer_to_delete) == _closing_connections.end()' failed.
Aborted (core dumped)