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Before this PR, the `wait_for_normal_state_handled_on_boot` would wait for a static set of nodes (`sync_nodes`), calculated using the `get_nodes_to_sync_with` function and `parse_node_list`; the latter was used to obtain a list of "nodes to ignore" (for replace operation) and translate them, using `token_metadata`, from IP addresses to Host IDs and vice versa. `sync_nodes` was also used in `_gossiper.wait_alive` call which we do after `wait_for_normal_state_handled_on_boot`. Recently we started doing these calculations and this wait very early in the boot procedure - immediately after we start gossiping (50e8ec77c6). Unfortunately, as always with gossiper, there are complications. In #14468 and #14487 two problems were detected: - Gossiper may contain obsolete entries for nodes which were recently replaced or changed their IPs. These entries are still using status `NORMAL` or `shutdown` (which is treated like `NORMAL`, e.g. `handle_state_normal` is also called for it). The `_gossiper.wait_alive` call would wait for those entries too and eventually time out. - Furthermore, by the time we call `parse_node_list`, `token_metadata` may not be populated yet, which is required to do the IP<->Host ID translations -- and populating `token_metadata` happens inside `handle_state_normal`, so we have a chicken-and-egg problem here. It turns out that we don't need to calculate `sync_nodes` (and hence `ignore_nodes`) in order to wait for NORMAL state handlers. We can wait for handlers to finish for *any* `NORMAL`/`shutdown` entries appearing in gossiper, even those that correspond to dead/ignored nodes and obsolete IPs. `handle_state_normal` is called, and eventually finishes, for all of them. `wait_for_normal_state_handled_on_boot` no longer receives a set of nodes as parameter and is modified appropriately, it's now calculating the necessary set of nodes on each retry (the set may shrink while we're waiting, e.g. because an entry corresponding to a node that was replaced is garbage-collected from gossiper state). Thanks to this, we can now put the `sync_nodes` calculation (which is still necessary for `_gossiper.wait_alive`), and hence the `parse_node_list` call, *after* we wait for NORMAL state handlers, solving the chickend-and-egg problem. This addresses the immediate failure described in #14487, but the test would still fail. That's because `_gossiper.wait_alive` may still receive a too large set of nodes -- we may still include obsolete IPs or entries corresponding to replaced nodes in the `sync_nodes` set. We need a better way to calculate `sync_nodes` which detects ignores obsolete IPs and nodes that are already gone but just weren't garbage-collected from gossiper state yet. In fact such a method was already introduced in the past:ca61d88764but it wasn't used everywhere. There, we use `token_metadata` in which collisions between Host IDs and tokens are resolved, so it contains only entries that correspond to the "real" current set of NORMAL nodes. We use this method to calculate the set of nodes passed to `_gossiper.wait_alive`. We also introduce regression tests with necessary extensions to the test framework. Fixes #14468 Fixes #14487 Closes #14507 * github.com:scylladb/scylladb: test: rename `test_topology_ip.py` to `test_replace.py` test: test bootstrap after IP change test: scylla_cluster: return the new IP from `change_ip` API test: node replace with `ignore_dead_nodes` test test: scylla_cluster: accept `ignore_dead_nodes` in `ReplaceConfig` storage_service: remove `get_nodes_to_sync_with` storage_service: use `token_metadata` to calculate nodes waited for to be UP storage_service: don't calculate `ignore_nodes` before waiting for normal handlers