Users Guide

Features in metro node
This chapter describes the specific features of metro node.
Topics:
• Metro node security features
• ALUA
• Provisioning with metro node
• Performance monitoring
• Notification
Metro node security features
The operating systems of the metro node management server and the directors are based on a Novell SUSE Linux Enterprise
Server 15 SP1 distribution.
The operating system has been configured to meet Dell EMC security standards by disabling or removing unused services, and
protecting access to network services through a firewall.
The metro node security features include:
● LDAP authentication using OS secure SSSD service
● HTTPS to access the metro node UI
● HTTPS inter-cluster link in a metro node Metro configuration
● SCP to copy files
● Support for separate networks for all metro node cluster communication
● Defined user accounts and roles
● Certificate Authority (CA) certificate (default expiration 5 years)
● Two host certificates (default expiration 2 years)
● External directory server support
CAUTION:
The WAN-COM inter-cluster link carries unencrypted user data. To ensure privacy of the data,
establish an encrypted VPN tunnel between the two sites.
For more information about security features and configuration see the Dell EMC Security Configuration Guide for metro node.
ALUA
Asymmetric Logical Unit Access (ALUA) routes I/O of the LUN directed to non-active/failed storage processor to the active
storage processor without changing the ownership of the LUN.
Each LUN has two types of paths:
● Active/optimized paths are direct paths to the storage processor that owns the LUN.
Active/optimized paths are usually the optimal path and provide higher bandwidth than active/non-optimized paths.
● Active/non-optimized paths are indirect paths to the storage processor that does not own the LUN through an
interconnect bus.
I/Os that traverse through the active/non-optimized paths must be transferred to the storage processor that owns the
LUN. This transfer increases latency and has an impact on the array.
Metro node detects the different path types and performs round robin load balancing across the active/optimized paths.
Metro node supports all three flavors of ALUA:
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