Dell MD3200I manual

Dell PowerV ault MD3200i and MD3220i Storage Array s Deployment Guide book.book Page 1 Sunday , September 11, 2011 10:24 PM[...]

Notes, Cautions, and W arnings NOTE: A NOTE indicates important information that helps you make b etter use of your computer . CAUTION: A CAUTION indicates potential damage to hardware or loss of data if instructions are not followed. WAR N IN G: A WARNING indicates a potential for property damage, personal injury , or death. ______________ ______ [...]

Contents 3 Contents 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . 7 Sy stem Requirements . . . . . . . . . . . . . . . . . . . 7 Management Station Requirements . . . . . . . . . 7 Introduction to Storage Array s . . . . . . . . . . . . . . 8 2 Hardware Installation . . . . . . . . . . . . . . . 11 Planning the Storage Configur ati[...]

4 Contents 3 Installing PowerV ault MD Storage Software . . . . . . . . . . . . . . . . . . . . . . . . . 27 Graphical Installation (Recommended) . . . . . . . 28 Console Installation . . . . . . . . . . . . . . . . . 30 Silent Installation . . . . . . . . . . . . . . . . . . 30 Upgrading PowerV ault MD Storage Software . . . . . 31 4 Post Installa[...]

Contents 5 Uninstalling PowerV ault MD Storage Software From Linux . . . . . . . . . . . . . . . . . . . . . . . . 54 A Appendix—Manual Configuration of iSCSI . . . . . . . . . . . . . . . . . . . . . . . . . . 55 Step 1: Discover the Storage Arr ay (Out-of-band Management Only) . . . . . . . . . . . . 56 Default Management Port Settings . . . . [...]

6 Contents Step 7: Connect to the T arget Storage Array From he Host Serv e r . . . . . . . . . . . . . . . . . . . . . . 70 Step 8: (Optional) Set Up In-Band Management . . . . . 74 B Appendix—Using Internet Storage Naming Service . . . . . . . . . . . . . . . . . . . . 75 C Appendix—Load Balancing . . . . . . . . . . 77 Load Balance Policy . [...]

Introduction 7 1 Introduction This guide provides in fo rmati on about deploying Dell P owerV ault MD MD3200i and Dell P owerV ault MD3220i storage arrays. The deployment process includes: • Hardwar e installation • Modular Disk Stora ge Manager (MDSM) software installation • Initial system configuration Other information provided include sys[...]

8 Introduction • Display resolution of 1024x768 with 16 million colors (1280x1024 32-bit recommended) • Microsoft W indows, Red Hat Ente rprise Linux, and SUSE Linux Enterprise Server . NOTE: Operating sy stem instal lations can be either native or hypervisor guest configurations. NOTE: Supported hypervisors include Micros oft Hyper -V , Citrix[...]

Introduction 9 Unconfigured capacity comprises of phy sical disks not already assigned to a disk group. When a virtual disk is cr eated using unconfigured capacity , a disk group is automatically created. If the only virtual disk in a disk group is deleted, the disk group is also deleted. F r ee capacity is space in a disk group that is not assigne[...]

10 Introduction book.book Page 10 Sunday, Sep tember 11, 2011 10:24 PM[...]

Hardware Installation 11 2 Hardware Installation Be fo re u s i n g t hi s gu id e, e ns ure th a t y ou rev ie w th e i ns t ru ct i on s i n t he : • Getting Started Guide —The Getting Started Guide that shipped with the storage array provides information to configure the initial setup of the system. • Planning section of the Owner ’s Ma [...]

12 Hardware Installation Connecting the Storage Array The storage array is connected to a host using two hot-swappable RAID controller modules. The R AID controll er modules ar e identifi ed as R AID controller module 0 and R AID controller module 1. Each R AID controll er module has four iSCSI In port connectors that provide Ethernet connections t[...]

Hardware Installation 13 Direct-Attached Configurations Y ou can connect the Ethernet ports of the host servers dir ectly to the storage array R AID controller module iSCSI ports. Single Path Data Configurations W ith a single path configuration, a group of heterogeneous hosts can be connected to the storage array through a single physical Ethernet[...]

14 Hardware Installation F igur e 2-1 shows a non-r edundant cabling configuration to the RAID controller modules using a sing le path data configuration. Figure 2-1. Four Hosts Connected to a Single Controller Corporate, public, or private network Storage array Server 1 Server 2 Server 3 Server 4 book.book Page 14 Sunday, Sep tember 11, 2011 10:24[...]

Hardware Installation 15 F igur e 2-2 shows two hosts connected to a single controller array . Figure 2-2. T wo Hosts Connected to a Single Controller Corporate, public, or private network Storage array Server 1 Server 2 book.book Page 15 Sunday, Sep tember 11, 2011 10:24 PM[...]

16 Hardware Installation F igur e 2-3 shows eight stand-alone hosts supported in a dual controller array configuration with a single data path. Figure 2-3. Eight Hosts in a Dual-Controller Configuration Corporate, public, or private network Storage array Server 1 Server 2 Server 3 Server 4 Server 8 Up to 8 hosts book.book Page 16 Sunday, Sep tember[...]

Hardware Installation 17 Dual-Path Data Configuration In F igur e 2-4, up to four servers ar e di re ctly attached to the R AID control ler modules. If the host server has a se co nd Ethernet connection to the array , it can be attached to the iSCSI port s on the array's second contr oller . This configuration provides improved av ai la bility[...]

18 Hardware Installation Figure 2-4. Four Hosts Connected to T wo Controllers Storage array Server 1 Server 2 Server 3 Server 4 Corporate, public, or private network book.book Page 18 Sunday, Sep tember 11, 2011 10:24 PM[...]

Hardware Installation 19 Figure 2-5. Four Hosts Connected in a Dual-Controller Configuration Corporate, public, or private netwo rk Storage array Four node cluster server book.book Page 19 Sunday, Sep tember 11, 2011 10:24 PM[...]

20 Hardware Installation Network-Attached Confi gurations Y ou can also cable the host servers to the RAID con troller modul e iSCSI ports through industry-standard 1GB Ethernet switches. An iSCSI config uration t h a t us e s Et he r n et sw i tc h es is f re q u e n t ly re f e r r e d t o as a n I P SA N . B y u s in g an IP SAN, the P owerV aul[...]

Hardware Installation 21 Figure 2-6. 64 Servers Connected to a Single Controller Corporate, public, or private network Up to 64 hosts Switch Storage array book.book Page 21 Sunday, Sep tember 11, 2011 10:24 PM[...]

22 Hardware Installation Figure 2-7. 64 Servers C onnected to T wo Controllers Corporate, public, or private network Switch Storage array Up to 64 hosts book.book Page 22 Sunday, Sep tember 11, 2011 10:24 PM[...]

Hardware Installation 23 Cabling PowerV ault MD1200 Series Expansion Enclosures Y ou can expand the capacity of your P o werV ault MD3200i series storage array by adding P owerV ault MD1200 series expansion enclosur es. Y ou can expand the physical disk pool to a maximum of 120 (or 192, if enabled using P remium F eature activation) physica l disks[...]

24 Hardware Installation a Install the software and driver package included on the P owerV ault MD series resource media. F or information about installing the software, see "Installing P owerV ault MD Storage Software" on page 25. b Update the storage array RAID controller module firmware and NVSRAM to the latest versions availabl e at s[...]

Hardware Installation 25 Expanding With New PowerV ault MD1200 Series Expansion Enclosures P erform the following steps to atta ch new P owerV ault MD1200 series expansion enclosur es to a P owerV ault MD3200i series sto r age array: 1 Before adding the e xpansion enclosure(s), ensure that the storage array software is installed and up to date. F o[...]

26 Hardware Installation c T ur n off any expansion enclosur e(s) in the affected system. 3 Cable the e xpansion enclosure(s) to the storage array . 4 T ur n on attached units: a T ur n on the expansion enclosure(s) . W ait for the enclosure status LED to turn blue. b T ur n on the storage array and wait for the status LED to indicate that the unit[...]

Installing PowerV ault MD Storage Software 27 3 Installing PowerV ault MD Storage Software The Dell P owerV ault MD series resource media contains software and drivers for both Linux and Microsoft W indows operating systems. The root of the media contains a readme.txt file covering changes to the software, updates, fixes, patches, and ot her import[...]

28 Installing PowerV ault MD Storage Software NOTE: If Dynamic Host Configuration Protocol (DHCP) is not used, initial configuration of the management station must be perform ed on the same phy sical subnet as the storage array . Additionally , during initial configuration, at l east one netwo rk adapter must be configured on the same IP subnet as [...]

Installing PowerV ault MD Storage So ftware 29 2 Select Install MD Storage Software. 3 Read and accept the license agreement. 4 Select one of the following ins talla tion options from the Install Set dropdown menu: • F ull (recommended)—Installs the P owerV ault MD Storage Manager (client)software, host-based stor age agent, multipath driver , [...]

30 Installing PowerV ault MD Storage Software NOTE: The MD Storage Manager installer automatically installs the required drivers, firmware, and operating sy stem patches/hotfixes to operate your storage array . These drivers and firmware are also available at support.dell.com . In addition, see the Support Matrix at support.dell.com/manuals for any[...]

Installing PowerV ault MD Storage So ftware 31 2 Modify the custom_silent.properties file to r eflect the featur es, models and installation opti ons to be used. Then, save the file. 3 Once the custom_sil ent.proper ties file is r evised, run the following command to begin the installation: ./mdss_install.bin –f <host_server_path>/custom_si[...]

32 Installing PowerV ault MD Storage Software book.book Page 32 Sunday, Sep tember 11, 2011 10:24 PM[...]

Post Installation T asks 33 4 Post Installation T asks Before using the storage array for the fi rst time, complete a number of initial configuration tasks in the order shown. These tasks ar e performed using the MD Storage Manager (MDSM) software. NOTE: If Dynamic Host Configurat ion Protocol (DHCP) is not used, initial configuration using the man[...]

34 Post Installation T asks iSCSI Configuration W orksheet The iSCSI configuration worksheet he lps you plan your configuration. Recording host server and storage array IP addresses at a single location enables you to configure your se tup faster and more efficiently . "Guidelines for Configuring Y our Network for iSCSI" on page 49 provid[...]

Post Installation T asks 35 IPv4 Settings Mutual CHAP Secret T arget CHAP Secret A B host server PowerV ault MD32 xx i 192.168.130.101 ( In 0 default) 192.168.131.101 (In 1 default ) 192.168.132.101 ( In 2 default) 192.168.133.101 ( In 3 default) 192.168.128.10 1 (management network po rt) 192.168.130.102 ( In 0 default) 192.168.131.102 ( In 1 defa[...]

36 Post Installation T asks IPv6 Settings Mutual CHAP T arget CHAP A B If you need addi tional space for more than one host server , use an additional sheet. Link local IP addr ess Routable IP addr ess Subnet prefix Gateway A host server Host iSCSI port 1 ___ . ___ . ___ . ___ ___ . ___ . ___ . ___ ___ . ___ . ___ . ___ ___ . ___ . ___ . ___ Link l[...]

Post Installation T asks 37 iSCSI controller 0, In 3 IP address Routable IP address 1 Routable IP address 2 Router IP address FE80 : 0000 : 0000 : 00 00 : ____ : ____ : ____ : ____ ____ : ____ : ____ : ____ : ____ : ____ : ____ : ____ ____ : ____ : ____ : ____ : ____ : ____ : ____ : ____ ____ : ____ : ____ : ____ : ____ : ____ : ____ : ____ iSCSI c[...]

38 Post Installation T asks Configuring iSCSI on Y our Storage Array The following sections contain step-b y-step instructions for configuring iSCSI on your storage array . However , before beginning, it is important to understand where each of these step s occur in relation to your host server/storage a rray environment. T able 4-2 below shows eac[...]

Post Installation T asks 39 Automatic Configuration Using the Modular Disk Configuration Utility NOTE: If PowerV ault MDCU is not installed, it can be insta lled from the PowerV ault MD series resource media. P owerV ault MDCU provides a consolidat ed approach for configuring the iSCSI network of host servers and iSCSI-base d storage arrays using a[...]

40 Post Installation T asks 4 Configure the IP protocols and addr esses for the management ports. 5 Configure the IP protocols and addresses for the iSCSI ports. 6 Specify the CHAP authentication method. 7 Apply the settings after re viewing a summary . 8 Repeat the process st arting from step 2 to configure additional arrays. Host Configuration (H[...]

Post Installation T asks 41 Ke ep the follow ing guidelines in mind for the st orage array an d host configuration: • F or optimal performance, ensure your network configur ation is valid by consulting the storage array's support matrix. • If your host has multiple network inte rfaces, it is recommended that each network interface uses a s[...]

42 Post Installation T asks • A utomatic Discovery—Automatic disco very queries the local sub-network for all iSCSI-based storage arrays and may take several minutes to complete. • Manu a l Discovery—Manu a l dis covery allo ws you to locate iSCSI-based storage arrays that are outside of the local sub-network. Manual discover y requir es se[...]

Post Installation T asks 43 If you have not selected Specify Configuration Manually for any of the two protocols, then you can skip s tep 8. 8 If you have selected Specify Configuration Manu ally for any of the two protocols in the last step, a series of screens showing the backend view image of the storage array controllers is displaye d. Each ima[...]

44 Post Installation T asks 15 If you selected Ye s in the last step, then the Select Storage Array screen is displayed. Select the storage array that you want to con figure for connectivity to the local host. NOTE: The storage array s configured by the utility are marked as Configuration Complete against their names in the list. This helps you to [...]

Post Installation T asks 45 Configure the Host Connectivity Using PowerVault MDCU T o configure the host co nnectivity for an iSCSI-based stora ge array(s) using P owerV ault MDCU: 1 Launch the utility (if it is not launched automaticall y) from the server which needs to be configured for access to the iSCSI-based storage array(s). This server must[...]

46 Post Installation T asks 7 In the Storage Array Login screen, in the Controlle r# column, select the iSCSI host port of the st orage array that needs to be configured and its IP address(es). In the Host Address column, from drop-d own menu list, select the host IP address that logs into th e iSCSI host port of the storage a rray . See "Sour[...]

Post Installation T asks 47 F or Microsoft W indows Server 2003, each list contains all availabl e host IP addresses r egardless of whether or not the address is able to communicate with the associated iSCSI port. Y ou mu st select the appropriate host IP addresses for each iSCSI port. Automatic Selection NOTE: The contents in this section do not a[...]

48 Post Installation T asks Post Connection Establishment Steps After iSCSI connectivity is establishe d between the host server(s) and the storage array , you can create virtual disks on the storage array using MDSM and these virtual disks can be utilized by the host server(s). F or more information about storage pla nning and using MDSM, see the [...]

Guidelines for Configuring Y our Network for iSCSI 49 5 Guidelines for Configuring Y our Network for iSCSI This section pro vides general guid elines for setting up your network environment and IP addresses for use with the iSCSI ports on your host server and storage array . Y our spe cific networ k environment may requir e differ ent or additional[...]

50 Guidelines for Configuring Y our Network for iSCSI 3 On the General tab (for a local area connection) or the Networking tab (for all other connections), select Internet P rotocol (TCP/IP) , and then click P roperties . 4 Select Use the following IP address and enter the IP address, subnet mask, and default gateway a ddresses. If you are using a [...]

Guidelines for Configurin g Y our Network for iSCSI 51 7 T o specify the location of the file that you want to import into the Lmhosts file, select Import LMHOSTS and then select the file in the Open dialog box. 8 Enable or disabl e NetBIOS ove r TCP/IP . If using Microsoft W indows Server 2008 Core V ersion, use the netsh interface command to conf[...]

52 Guidelines for Configuring Y our Network for iSCSI If you are using a static IP address (root users only): 1 Edit the / etc/sysconfig/network file as follows: NETWORKING=yes HOSTNAME=mymachine.mycompany.com GATEWAY=255.255.255.0 2 Edit the configuration file for the connection you want to configure, either /etc/sysconfig/network-scripts/ifcfg-et[...]

Uninstalling PowerV ault MD Storage Software 53 6 Uninstalling PowerV ault MD Storage Software Uninstalling Dell PowerV ault MD Storage Software From Windows Use the Change/R emov e P rogram featur e to uninstall Dell P owerV ault Modular Disk St orage Softwar e from Micr osoft W indows operating syst ems other than Microsoft W indows Server 2008: [...]

54 Uninstalling PowerV ault MD Storage Software NOTE: By default, Dell PowerVa ult MD St orage Manager is installed in the Program FilesDellMD Storage Software directory . If another directory was used during installation, navigate to that directory before beginning the uninstallation procedure. 2 F rom the installation directory , type the foll[...]

Appendix—Manual Configuration of iSCSI 55 A Appendix—Manual Configuration of iSCSI The following sections contain step-b y-step instructions for configuring iSCSI on your storage array . However , before beginning, it is important to understand where each of these steps occur in relation to your host server or storage array environment. T able [...]

56 Appendix—Manual Configuration of iSCSI Step 1: Discover the St orage Array (Out-of-band Management Only) Default Management Port Settings By default, the storage array management ports ar e set to Dynamic Host Configuration P rotocol (DHCP). If the controllers on your storage array ar e unable to get IP configuration from a DHCP server , it ti[...]

Appendix—Manual Configuration of iSCSI 57 Automatic Storage Array Discovery 1 Launch MD Storage Manager (MDSM). If this is the first storag e array to be set up, the Add New Storage Array window is displayed. 2 Select Automatic and click OK . It may take several minutes for the discovery process to complete. Closing the discovery status window be[...]

58 Appendix—Manual Configuration of iSCSI NOTE: Before configuring the storage array , check the status icons on th e Summary tab to ensure that the enclosures in the storage array are in an Optimal status. For more information on the status icons, see the Owner’ s Manual at support.dell.com/manuals . Step 2: Configure the iSCSI Ports on the St[...]

Appendix—Manual Configuration of iSCSI 59 Controller 1, Port 1: IP: 192.168.131.102 Subnet Mask: 255.255.255.0 Port: 3260 Controller 1, Port 2: IP: 192.168.132.102 Subnet Mask: 255.255.255.0 Port: 3260 Controller 1, Port 3: IP: 192.168.133.102 Subnet Mask: 255.255.255.0 Port: 3260 NOTE: No default gateway is set. T o configure the iSCSI po rts on[...]

60 Appendix—Manual Configuration of iSCSI 3 T o enable ICMP PING responses for all ports, select Enable ICMP PING responses. 4 Click OK when all iSCSI storage array port configurations are complete. 5 T est the connection by performing a ping command on each iSCSI storage array port. Step 3: Perform T arget Discovery From the iSCSI Initiator This[...]

Appendix—Manual Configuration of iSCSI 61 6 Click OK to exit the Advanced menu and click OK again to exit the Add Ta r g e t P o r t a l s screen. 7 To e x i t t h e Discovery tab, click OK . If you plan to configur e CHAP authentication , do not perform discovery on more than one iSCSI port at this point. Go to "Step 4: Configure Host Acces[...]

62 Appendix—Manual Configuration of iSCSI c V erify that the following time-out value is set to 30: node.session.timeo.replacement_timeout = 30 d Save and close the /etc/iscsi/iscsid.conf file. 5 F rom the console, restart the iSCSI service with the following command: service iscsi start 6 V erify that the iSCSI service is running during boot usi[...]

Appendix—Manual Configuration of iSCSI 63 5 Select the host type. 6 Select whether or not the host server will be part of a host server group that shares access to the same virtual dis ks as other host server s. Select Ye s only if the host is part of a Microsoft cluster . 7 Click Next . 8 Specify if this host will be p art of a host group. 9 Cli[...]

64 Appendix—Manual Configuration of iSCSI CHAP is an optional feature and is not r equired to use iSCSI. Howe ver , if you do not configure CHAP authentication, an y host server co nn ected to the same IP network as the storage array can read from and write to the storage array . NOTE: When using CHAP authentication, you should configure it on bo[...]

Appendix—Manual Configuration of iSCSI 65 Configuring T arget CHAP Authentication on the Storage Array 1 F rom MDSM, click the iSCSI tab and then click Change T arget Authenti cation . Select one of the CHAP settings described in T able A-4. 2 T o configure a CHAP secret, select CHAP and select CHAP Secret . 3 Enter the T arget CHAP Secret (or Ge[...]

66 Appendix—Manual Configuration of iSCSI Configuring Mutual CHAP Authen tication on the S torage Array The initiator secret must be unique for each host server that connects to the storage array and must not be the same as the target CHAP secret. Change the initiator authen tication settings in t he Change T arget Authenticat ion window . Use th[...]

Appendix—Manual Configuration of iSCSI 67 5 Under Ta r g e t P o r t a l s , select the IP addr ess of th e iSCSI port on the storage array and click Rem ov e . The iSCSI port you configured on the storage array during target discovery disappears. 6 Under T arget P ortals , click Add and re-enter the IP addr ess or DNS name of the iSCSI port on t[...]

68 Appendix—Manual Configuration of iSCSI 5 Remove the target portal that you configured on the storage array during target discovery : iscsicli RemoveTargetPortal <IP_address> <TCP_listening_port> 6 Add the tar get portal with CHAP defined: iscsicli QAddTargetPortal <IP_address_of_iSCSI_port_on_storage_array> [CHAP_username] [C[...]

Appendix—Manual Configuration of iSCSI 69 4 T o set up discovery session CHAP authentication, first uncomment the following line: discovery.sendtargets.auth.authmethod = CHAP 5 Set a user name and password for a discovery session CHAP authentication of the initiator by the target(s) by editing the following lines: discovery.sendtargets.auth.usern[...]

70 Appendix—Manual Configuration of iSCSI discovery.sendtargets.auth.username = iqn.1984- 05.com.dell:powervault.123456 discovery.sendtargets.auth.password_in = test1234567890 If you are using SUSE Linux Enterprise Server SP 3 using the GU I : 1 Click Desktop  Ya S T  iSCSI Initiator . 2 Click Service Start , then select When Booting [...]

Appendix—Manual Configuration of iSCSI 71 3 Click Log O n . 4 Select Automatically restore this connec tion when the system boots . 5 Select Enable multi-path . 6 Click Advanced and configure the follo wing settings under the General tab: • Loc al A da pt er —Must be set to Microsoft iSCSI Initiator . • Source IP —The source IP address of[...]

72 Appendix—Manual Configuration of iSCSI If you are using W indows Server 2008 Core V ersion : 1 Set the iSCSI initiator services to st art automatically (if not already set): sc <server_name> config msiscsi start= auto 2 Start the iSCSI service (if necessary): sc start msiscsi 3 Log on to the target: iscsicli PersistentLoginTarget <T[...]

Appendix—Manual Configuration of iSCSI 73 Fo r e x a m p l e , y o u r l o g o n c o mmand might look like this: iscsicli PersistentLoginTarget iqn.1984- 05.com.dell:powervault.6001372000ffe3332xx0000046 72edf2 3260 T 192.168.130.101 * * * 0x2 * * * * * * * * * 0 T o view ac t ive sessions to th e target, run the follow i ng command : iscsicli Se[...]

74 Appendix—Manual Configuration of iSCSI Step 8: (Optional) Set Up In-Band Management Out-of -band management (see "Step 1: Discover the Storage Array (Out-o f - band Management Only)" on page 56) is the recommended method for managing the storage array . However , to optionally set up in-band management, use the steps sho wn below . T[...]

Appendix—Using Internet Storage Naming Service 75 B Appendix—Using Internet Storage Naming Service Internet Stor ag e Naming Service (iSNS) server , supported only on Microsoft W indows iSCS I envir onments, eliminat es the need to manually configure each individual storag e array with a specifi c list of initiator s and targ et IP addresses. I[...]

76 Appendix—Using Internet Storage Naming Service book.book Page 76 Sunday, Sep tember 11, 2011 10:24 PM[...]

Appendix—Load Balancing 77 C Appendix—Load Balancing Load Balance Policy Multi-path drivers select the I/O path to a virtual disk through a specific RAID controller module. When the multi-path dr iver receives a new I/O to process, the driver tries to find a path to the current R AID controller module that owns the virtual disk. If the path to [...]

78 Appendix—Load Balancing Least Queue Dep th With Subset The least queue depth with subset policy is also kn own as the least I/Os or least request s policy . This policy routes the next I/O r equest to a data path that has the least outstanding I/O r equests queued. F or this policy , an I/O reques t is simply a comman d in the queue. The type [...]

Appendix—Load Balancing 79 T o change the load ba lance policy using W indows Server 2008 disk management: 1 F rom the desktop of the host, right-click My Computer and click Manage to open the Computer Management dialog. 2 Click Disk Management to show the list of virtual disks attached to the host. 3 Right-click on the virtual disk for wh ich yo[...]

80 Appendix—Load Balancing Figure C-1. Initiator Configurati on IP Addre sses Host If1: IP_Addr_If1 If2: IP_Addr_If2 MD32 xx i Controller 0 P0: IP_Addr_C0_P0 P1: IP_Addr_C0_P1 P2: IP_Addr_C0_P2 P3: IP_Addr_C0_P3 MD32 xx i Controller 1 P0: IP_Addr_C1_P0 P1: IP_Addr_C1_P1 P2: IP_Addr_C1_P2 P3: IP_Addr_C1_P3 TCP Connections To M D 3 2 xx i Controlle[...]

Appendix—Load Balancing 81 T wo sessions with one TCP connection are configured from the host to each controller (one session per port), for a to tal of four sessions. The multi-path failover driver balances I/ O access across the sessions to the ports on the same controller . In a duplex configuration, with virtual disks on each controller , cre[...]

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Appendix—Stopping and Starting iS CSI Services in Linux D Appendix—Stopping and Starting iSCSI Services in Linux T o manual ly stop the iS CS I services in Linux, certain steps must be followed to maintain parallel proces sing between the storage a rray and the host server . 1 Stop all I/O . 2 Unmount all correlated file systems. Stop iSCSI ser[...]

84 Appendix—Stopping and Starting iS CSI Services in Linux book.book Page 84 Sunday, Sep tember 11, 2011 10:24 PM[...]