Figure 117 Multipath Connection (Active-Active Connection) (When A Nas Connection Is Used) - Fujitsu ETERNUS DX S5 Series Design Manual

5. Connection Configuration
NAS Connection
During the operation phase
• During a multipath connection, if a failover or a failback is performed due to a controller failure or a
path error, the path that is being accessed becomes temporarily offline and the access path switch
occurs.
While the access path is being switched, NFS access sessions can continue the current connection, but
CIFS access sessions are temporarily disconnected. In addition, even for NFS access, a timeout may occur
depending on the retry count setting and the session may be disconnected.
• If paths are switched during CIFS access, wait for a while and try again. Note that access can be
immediately resumed by issuing a command (such as dir) that checks drives.
• The failover function for the NAS interface (NIC-CA) does not work if the operation management LAN
ports (MNT port/RMT port) have failed.
• An NFS access error or a response failure may occur in the following cases.
- When the IP address of the NAS port is taken over due to a failover or a failback
- When a NAS user volume or NAS backup volume is mounted or unmounted
• If the ETERNUS DX is used as a VMware datastore, the IP address of the NAS port may be taken over due
to a failover or a failback, and the following events may occur during a VM snapshot acquisition.
- Virtual machines are powered off, rebooted, or enter a unresponsive state.
- VM snapshot acquisitions fail.
- OS installations to virtual machines fail.
If problems such as these occur, check that a failover or failback is not being performed for the IP
address of the ETERNUS DX, and reboot the virtual machine or perform the failed operation again.
Figure 117 Multipath Connection (Active-Active Connection) (When a NAS Connection Is Used)
Client
LAN
192.168.2.1
Port Port
NIC-CA
CM#0
Note
During the operation phase
If an error occurs on one of the two ports that are set for redundancy by the multipath connection settings
and the path cannot be accessed, the IP address is taken over by the other port.
For example, when a controller or NIC-CA error occurs on the CM#0 side (IP address: 192.168.2.1) in the
connection configuration shown in
192.168.2.2) takes over the processes for the CM#0 side and receives access to both 192.168.2.1 and
192.168.2.2.
Client
LAN
LAN
192.168.2.2
Port Port
NIC-CA
CM#1
NAS
Volume
ETERNUS DX
Figure 117, the paired ports on the CM#1 side (IP address:
223 Design Guide