addition to checkpointing it also receives a stream of edits from the namenode and maintains its own in-memory copy of the namespace, which is always in sync with the active namenode namespace state. only one backup node may be registered with the namenode at once. prerequisites the following documents...
a vacuum (i.e., in a vessel operating at sub-atmospheric pressure). depending on the type of vacuum system (fig. ) and the required operating vacuum level, different vacuum gauges [...] vacuum valves – types and operation vacuum valves are an essential component in any vacuum system. there are a variety...