Nfs cluster-specific issues, Non cluster aware file sharing protocols, Adding new storage to a cluster – HP ProLiant SB460c SAN Gateway Storage Server User Manual

Page 104: 104 adding new storage to a cluster

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NFS cluster-specific issues

For convenience, all suggestions are listed below:

Back up user and group mappings.
To avoid loss of complex advanced mappings in the case of a system failure, back up the mappings
whenever the mappings have been edited or new mappings have been added.

Map consistently.
Groups that are mapped to each other should contain the same users and the members of the
groups should be properly mapped to each other to ensure proper file access.

Map properly.
• Valid UNIX users should be mapped to valid Windows users.
• Valid UNIX groups should be mapped to valid Windows groups.
• Mapped Windows user must have the “Access this computer from the Network privilege” or

the mapping will be squashed.

• The mapped Windows user must have an active password, or the mapping will be squashed.

In a clustered deployment, create user name mappings using domain user accounts.
Because the security identifiers of local accounts are recognized only by the local server, other
nodes in the cluster will not be able to resolve those accounts during a failover. Do not create
mappings using local user and group accounts.

In a clustered deployment, administer user name mapping on a computer that belongs to a trusted
domain.
If NFS administration tasks are performed on a computer that belongs to a domain that is not
trusted by the domain of the cluster, the changes are not properly replicated among the nodes in
the cluster.

In a clustered deployment, if PCNFS password and group files are being used to provide user
and group information, these files must be located on each node of the system.
Example: If the password and group files are located at c:\maps on node 1, then they must also
be at c:\maps on node 2. The contents of the password and group files must be the same on
both nodes as well.
These password and group files on each server node must be updated periodically to maintain
consistency and prevent users or groups from being inadvertently squashed.

Non cluster aware file sharing protocols

Services for Macintosh (SFM), File and Print Services for NetWare, HTTP file sharing protocols are
not cluster aware and will experience service interruption if installed on a clustered resource during
failover events of the resource. Service interruptions will be similar to those experienced during a
server outage. Data that has not been saved to disk prior to the outage will experience data loss. In
the case of SFM, it is not supported because SFM maintains state information in memory. Specifically,
the Macintosh volume index is located in paged pool memory. Using SFM in clustered mode is not
supported and may result in data loss similar in nature to a downed server should the resource it is
based on fails over to the opposing node.

Adding new storage to a cluster

Present the new storage to one node in the cluster. This can be accomplished through selective storage
presentation or through SAN zoning.

Cluster administration

104

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