Have two hosts, snert (DC) and pintsize (slave). Have them running as normal, so that e.g.

[snert:9999 /] cd /host=pintsize/server-config=newServer2
[snert:9999 /host=pintsize/server-config=newServer2] ls

works as expected

Then shut down the whole AS7 processes on pintsize (Ctrl-C).

Both cli (ls command from above) and Json access (http://snert:9990/domain-api/host/pintsize/server-config/newServer2 ) are hanging

Console log on snert shows

[Host Controller] 10:34:04,914 ERROR [stderr] (pool-6-thread-22) Exception in thread "pool-6-thread-22" java.lang.RuntimeException: Failed to execute operation
[Host Controller] 10:34:04,914 ERROR [stderr] (pool-6-thread-22) at org.jboss.as.controller.client.AbstractModelControllerClient$1.run(AbstractModelControllerClient.java:99)
[Host Controller] 10:34:04,914 ERROR [stderr] (pool-6-thread-22) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
[Host Controller] 10:34:04,914 ERROR [stderr] (pool-6-thread-22) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
[Host Controller] 10:34:04,915 ERROR [stderr] (pool-6-thread-22) at java.lang.Thread.run(Thread.java:680)
[Host Controller] 10:34:04,915 ERROR [stderr] (pool-6-thread-22) Caused by: java.net.ConnectException: Connection refused
[Host Controller] 10:34:04,915 ERROR [stderr] (pool-6-thread-22) at java.net.PlainSocketImpl.socketConnect(Native Method)
[Host Controller] 10:34:04,915 ERROR [stderr] (pool-6-thread-22) at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:351)
[Host Controller] 10:34:04,915 ERROR [stderr] (pool-6-thread-22) at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:213)
[Host Controller] 10:34:04,915 ERROR [stderr] (pool-6-thread-22) at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:200)
[Host Controller] 10:34:04,916 ERROR [stderr] (pool-6-thread-22) at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:432)
[Host Controller] 10:34:04,916 ERROR [stderr] (pool-6-thread-22) at java.net.Socket.connect(Socket.java:529)
[Host Controller] 10:34:04,916 ERROR [stderr] (pool-6-thread-22) at org.jboss.as.protocol.ProtocolClient.connect(ProtocolClient.java:87)
[Host Controller] 10:34:04,916 ERROR [stderr] (pool-6-thread-22) at org.jboss.as.protocol.mgmt.ManagementRequestConnectionStrategy$EstablishConnectingStrategy.getConnection(ManagementRequestConnectionStrategy.java:110)
[Host Controller] 10:34:04,916 ERROR [stderr] (pool-6-thread-22) at org.jboss.as.protocol.mgmt.ManagementRequest.execute(ManagementRequest.java:84)
[Host Controller] 10:34:04,916 ERROR [stderr] (pool-6-thread-22) at org.jboss.as.controller.client.AbstractModelControllerClient$1.run(AbstractModelControllerClient.java:84)
[Host Controller] 10:34:04,917 ERROR [stderr] (pool-6-thread-22) ... 3 more
[Host Controller] 10:34:47,990 ERROR [stderr] (pool-6-thread-29) Exception in thread "pool-6-thread-29" java.lang.RuntimeException: Failed to execute operation
[Host Controller] 10:34:47,991 ERROR [stderr] (pool-6-thread-29) at org.jboss.as.controller.client.AbstractModelControllerClient$1.run(AbstractModelControllerClient.java:99)
[Host Controller] 10:34:47,991 ERROR [stderr] (pool-6-thread-29) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
[Host Controller] 10:34:47,991 ERROR [stderr] (pool-6-thread-29) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
[Host Controller] 10:34:47,991 ERROR [stderr] (pool-6-thread-29) at java.lang.Thread.run(Thread.java:680)
[Host Controller] 10:34:47,991 ERROR [stderr] (pool-6-thread-29) Caused by: java.net.ConnectException: Connection refused
[Host Controller] 10:34:47,992 ERROR [stderr] (pool-6-thread-29) at java.net.PlainSocketImpl.socketConnect(Native Method)
[Host Controller] 10:34:47,992 ERROR [stderr] (pool-6-thread-29) at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:351)
[Host Controller] 10:34:47,992 ERROR [stderr] (pool-6-thread-29) at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:213)
[Host Controller] 10:34:47,992 ERROR [stderr] (pool-6-thread-29) at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:200)
[Host Controller] 10:34:47,992 ERROR [stderr] (pool-6-thread-29) at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:432)
[Host Controller] 10:34:47,992 ERROR [stderr] (pool-6-thread-29) at java.net.Socket.connect(Socket.java:529)
[Host Controller] 10:34:47,992 ERROR [stderr] (pool-6-thread-29) at org.jboss.as.protocol.ProtocolClient.connect(ProtocolClient.java:87)
[Host Controller] 10:34:47,992 ERROR [stderr] (pool-6-thread-29) at org.jboss.as.protocol.mgmt.ManagementRequestConnectionStrategy$EstablishConnectingStrategy.getConnection(ManagementRequestConnectionStrategy.java:110)
[Host Controller] 10:34:47,992 ERROR [stderr] (pool-6-thread-29) at org.jboss.as.protocol.mgmt.ManagementRequest.execute(ManagementRequest.java:84)
[Host Controller] 10:34:47,993 ERROR [stderr] (pool-6-thread-29) at org.jboss.as.controller.client.AbstractModelControllerClient$1.run(AbstractModelControllerClient.java:84)
[Host Controller] 10:34:47,993 ERROR [stderr] (pool-6-thread-29) ... 3 more

See also JBAS-9175