General Basic Requirements for SFT III

(Last modified: 15Jan2003)

This document (10011977) is provided subject to the disclaimer at the end of this document.

goal

fact

Formerly TID 2923372

Novell NetWare 3.11

Novell NetWare 4.1

Novell NetWare 4.11

Novell IntraNetWare 4.11

Novell NetWare 4.2

fix

Equipment: Always use Novell certified systems.
See http://developer.novell.com/npp/advanced.htm for certification bulletins.

Interrupts:

Priorities: Intel architecture implemented hardware Interrupts in the following from highest priority to lowest:

0, 1, (2/9), 10, 11, 12, 13, 14, 15, 3, 4, 5, 6, 7

This order is due to the Primary and Secondary interrupt controllers and how the secondary interrupt controller cascades off of the primary interrupt controller.

Default Interrupt assignments:

Below are the standard defaults for IRQs and how they are commonly used in the industry.

        0 = System Timer
        1 = Keyboard Data Ready
        2 = Video
        3 = Serial Communication (Comm 2)
        4 = Serial Communication (Comm 1)
        5 = Parallel Port 2
        6 = Diskette Controller
        7 = Parallel Port 1
        8 = Cmos Real - Time Clock
        9 = Tied to IRQ 2
        10 = Reserved
        11 = Reserved
        12 = Pointing Device
        13 = Math Coprocessor Exception
        14 = Hard Disk Controller
        15 = Reserved

Edge trigger vs Level trigger:

Definitions:
Edge Trigger: Interrupt may NOT be shared with another device.
Level Trigger: Interrupt may BE shared with another device.

Note: When using "Level Trigger" interrupts, only share the interrupt with exact types of devices. Example, two NE3200.LAN cards or two AHA- 2940 HBA devices. Do NOT share devices that are not identical.

Configuring Interrupts on SFT III:

NetWare SFT III needs to have the following devices configured in the following manner, assuming common devices only share IRQ's with identical type of devices. ie.. LAN cards can be configured to share interrupts with other LAN cards but not MSL cards or DISK controllers.

        MSL need the highest priority interrupt, (2/9), 10 ,11
        DISK need second highest priority interrupt; 12, 14 ,15
        LAN need least highest priority interrupt ; 3, 4 ,5 ,7

By configuring devices in the manner above, the MSL card will have the highest priority available followed by Disk controllers and LAN cards.

Note: Interrupt 7 and 15 are also used for the following Messaging:
Primary interrupt controller detected a lost hardware interrupt.
Secondary interrupt controller detected a lost hardware interrupt.

These messages are a result of a device issuing a IRQ, but is not there when the operating system goes to service it. If these types of messages are displayed on the server console, reconfigure hardware so that IRQ 7 and 15 are not being used by a MSL, DISK, or LAN controller. This does not mean that the device on IRQ 7 or 15 is the device directly responsible for the message, but may help troubleshoot the problem.

PCI 2.0 vs.2.1 vs. EISA

PCI is the latest technology for bus implementation.. It is suggested that all devices in each system be PCI spec v2.1. This includes System board, MSL, HBA, and NIC cards. However EISA is a proven technology and will provide for a stable environment.

LAN (Local Area Network)

Topology Ethernet vs. Token Ring

Token Ring Topology is a Token passing technology that works well in environments where the token can be passed to each node to provide equal opportunity for each node to send a packet on the network.

Ethernet Topology is a bus technology which will allow any node on the network to send a packet on the network as long as no other node is currently sending a packet.

Because Ethernet does not require a token to communicate on the network, the Ethernet topology will work more efficiently. If you are in a Token Ring environment and need to install a SFT III server, it is suggested that a router be added which will route from Token Ring to Ethernet where the SFT III server will be located.

LAN Health Packet

SFT III servers generate both "I'm alive" packets that are sent over IPX between the two servers and "LAN health" that are sent between IOEngines and any router on the network. (NOTE: "LAN health" packets are also known as "Status Check" packets.)

"LAN health" packets are used by the OS to determine if the LAN boards are functioning correctly. If one SFT III server has more functional LAN boards than the other, then it can become the primary server (setable with SET parameters). The IOEngine with the fewest number of band LAN adapters will become the primary machine.

"LAN health" packets are sent over all of the LAN boards in the SFT III server configuration. The associated acknowledges are also sent over all boards.

The "LAN health" packets can be suppressed by a SET parameter:

"SET Use Diagnostic Responder To Validate LAN Functionality = on"

A LAN health packet is sent to a router which will in turn sends the packet back to the source IOEngine. The LAN Health Packet is sent on every LAN card and every frame type to determine the health of the LAN for each IOEngine

Also see: TID2500198

I'm Alive Packet

SFT III servers generate "I'm alive" packets that are sent over IPX between the two servers.

"I'm alive" packets are used to verify that the other SFT III server is functioning. The OS uses them to make sure the MSL is working. For example, if "I'm alive" packets are received and the MSL has timed out then the OS knows that there is an MSL problem and not a total server failure.

The OS tries to send "I'm alive" packets every tick (approximate. 50 millisecond intervals) or 18 per second. The receiving server replies with an "I'm alive" acknowledge packet.

If there are multiple IPX routes between the SFT III servers, the "I'm alive' packets may follow different routes each time to get to the other SFT III server. This means that if multiple LAN boards are installed in the SFT III servers, the "I'm alive" packets can be sent on any one of the boards.

Only one "I'm alive" packet is sent even though there are multiple boards that may be bound to IPX. The acknowledge for the "I'm alive" packet may be sent on an IPX route different from the one on which it was received. This is purely a function of which IPX route was determined to be the "best" route by the LSL.
Destination of the "I'm Alive Packet" is to other IOEngine. Sent once a Tick (1/18 of a second) on the first LAN card that is loaded to ensure that both IOEngines are active and functional.

Also see: Sample Lanalyzer trace of "I'm Alive Packet"
Also see: TID2500198

MSL (Mirrored Server Link)

MSL Cards:
Always use MSL cards of equal revision level in both machine, this is also true for MSL drivers.

See the Novell Labs page for certification information on MSL cards. LABS.NOVELL.COM/INFOSYS/MASTR_08.HTML

Throughput

The MSL link between the two physical machines is the key element to SFT III. The MSL must be capable of handling all traffic from all LAN card and also the HBA in the machines. It is possible for one or more LAN cards configured at 100 Mbps to overrun the MSL. The sum of all throughput of all LAN cards must not exceed the capability of the MSL.

Example:
Add the speed of all LAN segments to see if the sum does not exceed the capability of the MSL card.

                10Mbs Ethernet segment #1
                10Mbs Ethernet segment #2
                10Mbs Ethernet segment #3

                =30Mbs

This example should not overrun a 100Mbs MSL card because the total of all LAN segment does not exceed the capability of the MSL card.. However if the sum of all LAN segments were to be greater than the though put of the MSL, the stability of the SFTIII pair will be compromised and exhibit many different behaviors such as server lock-ups, secondary server re-boots.

Active vs. Standby

NetWare SFTIII is designed to allow one active MSL card and up to seven additional standby MSL cards. If the active MSL card fails, then the next MSL card will attempt to become active after a restart and it is determined that the first MSL pair are not functional. (Note: the order that the MSL drivers are loaded dictates the order that the redundant MSL cards will become active).

HBA (Host Bus Adapter)

NetWare Mirroring

Implementation is the same as Native NetWare.

NetWare Duplexing

Implementation is the same as Native NetWare.

NCF Files

The load order for NetWare SFTIII NCF files are as follows:

        IOSTART.NCF
        MSSTART.NCF
        MSAUTO.NCF
        IOAUTO.NCF

Load order for HBA, LAN, MSL

If there are problems with LAN/MSL load order dependencies, load all drivers in the IOSTART.NCF in the order listed here:

        LOAD HBA drivers
        LOAD LAN drivers
        BIND protocols to LAN
        LOAD MSL drivers

If there are any dependencies to INITSYS.NCF (INETCFG.NLM), remark out the statements from IOAUTO.NCF.

document

Document Title:	General Basic Requirements for SFT III
Document ID:	10011977
Solution ID:	4.0.3106666.2235653
Creation Date:	17Jul1999
Modified Date:	15Jan2003
Novell Product Class:	Groupware NetWare

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