090-091 全真模擬試験 DEMO

問題5: The Split-Brain Avoidance (SBA) cable is:
A. A standard RS-232 null-modem cable only requiring signals Transmit, Receive, and signal-
Ground
B. A standard RS-232 null-modem cable requiring all 25-pins to be connected
C. A standard RS-232 null-modem cable requiring the minimum 9 pins found in a DB-9 connector
D. A special cable that can only be purchased from a UnixWare 7 NonStop Clusters OEM
正解: A
6. The name for the file that contains the list of load leveling parameters is:
A. /etc/cluster/load_level_parameters
B. /etc/load_level/parameters
C. /etc/cluster/load_level/parameters
D. /etc/cluster/load_level/parms
正解: C
7. You should choose CNM as your protected storage method when:
A. You want the fastest possible disk I/O performance
B. You want the lowest-possible window of vulnerability when a node fails
C. You are willing and able to accept the slower write performance and greater window of
vulnerability to reduce the price of the cluster
D. You dont care about the price of the cluster
正解: C
8. Which statement best describes the condition known as split brain and the measures required
to
prevent it from occurring?
A. Split brain occurs when two nodes perform the same task in parallel and come up with a
different result. The way to avoid split brain condition is to add a third node to the cluster,
performing the same task, serving as a tie-breaker. That is, whichever solution gets two votes,
wins.
B. Split brain occurs when two nodes each try to serve the same CVIP from their own LAN cards.
The way to prevent a split brain condition is to place a split brain avoidance node on the LAN
which will tell a node when it should serve the CVIP .
C. Split brain occurs when two nodes each think they should be the root node at the same time. In
the case of CNM, this causes filesystem corruption. In the case of external storage, this can cause
ping-pong panics. The way to prevent a split brain condition is to install a serial cable between the
two potential root nodes and configure split brain avoidance during the UnixWare 7 NonStop
Clusters installation procedure. Alternately, you can use a SAN configuration that can detect the
different between a node with a bad SAN connection and a node that is not functioning at all.
D. Split brain is when two processes are migrated by the load-balancing daemon and the
processes start to ping-pong between nodes because of incorrectly configured load-balancing
metrics. The way to prevent a split brain condition is to configure load balancing metrics properly.
正解: C
9. Which statement best describes what SSI means to an administrator of UnixWare 7 NonStop
Clusters?
A. Each node in the cluster is administered separately
B. The entire cluster is administered as a single computing resource, except where an operation
must be node-specific, such as shutting down a single node
C. The entire cluster is administered as a single computing resource, without exception
D. SSI is not implemented by UnixWare 7 NonStop Clusters
正解: B
10. In clustering, a protected resource is one that:
A. Has special circuits that keep if from being damaged during a voltage surge
B. Is monitored by special hardware such that if it should fail, support engineers will be notified
immediately that it needs to be replaced
C. Is monitored by special software to insure that it is not over-used
D. Is redundant in a cluster to avoid a single point of failure (SPF) and is automatically pressed
into service by the cluster in the event the primary component fails
正解: D