@Lari Hotari @David K

ERROR org.apache.bookkeeper.bookie.Bookie - Couldn't register bookie with zookeeper, shutting down : 
java.util.concurrent.ExecutionException: java.io.IOException: org.apache.bookkeeper.bookie.BookieException$MetadataStoreException: java.io.IOException: ZK exception checking and wait ephemeral znode /ledgers/available/pulsar-bookkeeper1-5.pulsar-bookkeeper1.pulsar.svc.cluster.local:3181 expired
	at java.base/java.util.concurrent.FutureTask.report(Unknown Source) ~[?:?]
	at java.base/java.util.concurrent.FutureTask.get(Unknown Source) ~[?:?]
	at org.apache.bookkeeper.bookie.BookieImpl.start(BookieImpl.java:740) ~[org.apache.bookkeeper-bookkeeper-server-4.17.2.jar:4.17.2]
	at org.apache.bookkeeper.proto.BookieServer.start(BookieServer.java:135) ~[org.apache.bookkeeper-bookkeeper-server-4.17.2.jar:4.17.2]
	at org.apache.bookkeeper.server.service.BookieService.doStart(BookieService.java:89) ~[org.apache.bookkeeper-bookkeeper-server-4.17.2.jar:4.17.2]
	at org.apache.bookkeeper.common.component.AbstractLifecycleComponent.start(AbstractLifecycleComponent.java:83) ~[org.apache.bookkeeper-bookkeeper-common-4.17.2.jar:4.17.2]
	at org.apache.bookkeeper.common.component.LifecycleComponentStack.lambda$start$4(LifecycleComponentStack.java:144) ~[org.apache.bookkeeper-bookkeeper-common-4.17.2.jar:4.17.2]
	at com.google.common.collect.ImmutableList.forEach(ImmutableList.java:422) [com.google.guava-guava-32.1.2-jre.jar:?]

i ran into an error when upgrading the bookies for one clsuter ? it seems hung. there. can u suggest ?