of 16
7/31/2019 3103047 16 Storage Area Networks
1/16
ESX Server System Management IIModule 6
Storage Area NetworksSAN Concepts
Hardware Compatibility
Configuration for ESX Server
SAN Failover
7/31/2019 3103047 16 Storage Area Networks
2/16
2
For ESX Server 2.0.1 2003-11-05Copyright 2003 VMware, Inc. All rights reserved.
2
Storage Area Networks, Network-Attached Storage
Host Host
Fileserver
NFS or SMB IP LAN or WAN links
SCSI Fibre Channel copper or fiber media
Diskarray +
intelligentcontroller
SAN NAS
Host Host
7/31/2019 3103047 16 Storage Area Networks
3/16
3
For ESX Server 2.0.1 2003-11-05Copyright 2003 VMware, Inc. All rights reserved.
3
ESX Server, SAN, and NAS
VMkernel cannot use virtual disks on NAS Because VMkernel does not know NFS or SMB
NAS can be used for /vmimages -type storage Dont forget to export virtual disks!
VMkernel can use virtual disks on a SAN VM storage is centralized for easy management
Required for clustering between VMs on different ESX Servers
VMkernel can also use raw LUNs on a SAN Required for physical-to-virtual clustering
7/31/2019 3103047 16 Storage Area Networks
4/16
4
For ESX Server 2.0.1 2003-11-05Copyright 2003 VMware, Inc. All rights reserved.
4
Parts of Fibre Channel SAN
Host Bus Adapter (HBA) This card connects the server to the FC network
Disk Array with Intelligent Controller(s) Supports the creation of volumes at various RAID levels
Controllers are often called storage ports or storageprocessors (SPs)
SAN Switches
Intelligent devices that interconnect HBAs and SPs Other devices
Tape drives, jukeboxes may also be connected to a SAN switch
7/31/2019 3103047 16 Storage Area Networks
5/16
5
For ESX Server 2.0.1 2003-11-05Copyright 2003 VMware, Inc. All rights reserved.
5
SAN Topology: Direct
Server
HBA
Storage
SP
Low cost
No expansion without systemshutdown
No redundancy; many single points
of failure
7/31/2019 3103047 16 Storage Area Networks
6/16
6
For ESX Server 2.0.1 2003-11-05Copyright 2003 VMware, Inc. All rights reserved.
6
SAN Topology: Trivial Fabric
Server
HBA
FC Switch
Storage
SP
Switch allows for later connectionof more storage or more servers(robust topology)
No redundancy; many single pointsof failure
7/31/2019 3103047 16 Storage Area Networks
7/167
For ESX Server 2.0.1 2003-11-05Copyright 2003 VMware, Inc. All rights reserved.
7
SAN Topology: Arbitrated Loop (FCAL)
Splits transmit and receive into twophysical connections
Similar to a Token Ring dataconfiguration
Not supported by ESX Server
Server
HBA
Server
HBA
Storage
SP
7/31/2019 3103047 16 Storage Area Networks
8/168
For ESX Server 2.0.1 2003-11-05Copyright 2003 VMware, Inc. All rights reserved.
8
SAN Topology: Fabric with Multipath
FC Switch
Server
HBA HBA
Server
HBA HBA
StorageSP SP
7/31/2019 3103047 16 Storage Area Networks
9/169
For ESX Server 2.0.1 2003-11-05Copyright 2003 VMware, Inc. All rights reserved.
9
SAN Concepts
SAN devices are identified by a World Wide Number
Unique, 64-bit address assigned to each piece of Fibre Channelequipment: 210000e08b05672d
A LUN (logical unit number) Identifies individual units of storage behind a SCSI target ID: a RAID
group or a single disk drive Switched fabric SANs are partitioned into zones
Member devices cannot communicate across zone boundaries
Zoning is implemented in terms of switch ports (hard) or WWN (soft)
7/31/2019 3103047 16 Storage Area Networks
10/1610
For ESX Server 2.0.1 2003-11-05Copyright 2003 VMware, Inc. All rights reserved.
10
ESX SAN Hardware Compatibility
HBAs: QLogic 2200, 2300 series (including OEMed HP cards)
Emulex 8000, 9000 series
Switches: Brocade Silkworm, others
Storage: IBM FAStT, ESS (Shark); HP MSA, EVA; EMC Symmetrix
Fujitsu-Siemens S60; HP XP; Hitachi(clustering configurations not yet supported)
EMC Clariion(failover and clustering configurations not yet supported)
Work closely with pre-sales or support!
7/31/2019 3103047 16 Storage Area Networks
11/1611
For ESX Server 2.0.1 2003-11-05Copyright 2003 VMware, Inc. All rights reserved.
11
Key ESX Server configuration checks
Because LUNs may be discontiguous Ensure that DiskSupportSparseLUN is 1
Because VMkernel by default only scans LUNs
up to 7 Set DiskMaxLUN to desired maximum
Caution: large values will slow boot markedly
Use DiskMaskLUNs to control LUN visibilityvmhba0:0:4,6-255;
Because masking overridesmax LUN
7/31/2019 3103047 16 Storage Area Networks
12/1612
For ESX Server 2.0.1 2003-11-05Copyright 2003 VMware, Inc. All rights reserved.
12
SAN Configuration Tips
Set DiskRetryUnitAttention to 1 if connecting to IBM FAStT On FAStT storage, unit attention signals can be noncritical
Some HBAs require further configuration Example: QLogic cards:
If IBM storage:Set Port Down Retry Count to 8If clustering:
Set Enable Target Reset to YesSet Full LIP Login to YesSet Full LIP Reset to No
Check the release notes!
7/31/2019 3103047 16 Storage Area Networks
13/1613
For ESX Server 2.0.1 2003-11-05Copyright 2003 VMware, Inc. All rights reserved.
13
Making SAN storage available to VMs
Scan for new LUNs with MUI or command linevmkfstools s vmhba0
No need to reboot or shut down VMs
When rescanning QLogic adapters from command line, youmust first clear the cards cache of LUNsecho scsi-qlascan > /proc/scsi/qla2 ?00/ number
Allocate Fibre Channel HBAs only to VMkernel To administer, use VMware Management Interface or vmkfstools
Do not rescan SCSI adapters
7/31/2019 3103047 16 Storage Area Networks
14/1614
For ESX Server 2.0.1 2003-11-05Copyright 2003 VMware, Inc. All rights reserved.
14
ESX Server 2.0.1 and Multipathing
Multipathing allows a SAN LUN to continue to beavailable in the event of a hardware failure Manual load-balancing support in ESX 2.0: administrator
may set preferred paths for each LUN
ESX Server supports failover with any supportedHBAs Failover occurs automatically, with a 30-60 second delay
7/31/2019 3103047 16 Storage Area Networks
15/1615
For ESX Server 2.0.1 2003-11-05Copyright 2003 VMware, Inc. All rights reserved.
15
Setting Preferred Paths
View list of paths to storage# cat /proc/vmware/scsi/vmhba0/0:1[]Paths:fixedvmhba0:0:1 on*#vmhba1:0:1 on
Set your desired policy
echo "preferred vmhba1:0:1" > 0:1echo "policy mru" > 0:1
Save with vmkmultipath -S
Active
Preferred
7/31/2019 3103047 16 Storage Area Networks
16/16
ESX Server System Management IIModule 6
Questions?