To connect a server,
1. Install the server as directed by the appropriate hardware installation guide.
2. Install the operating system and other required software (see the CTOS System Administration Guide).
3. Set the server for the appropriate cluster speed: 307 Kbps, 1.8 Mbps, or 3.7 Mbps. See the CTOS System Administration Guide for
instructions on how to do this. Make sure that the server and all the workstations in the cluster can support the selected speed.
4. Connect the cluster cables to the workstations and to the server, but do not power on the workstations or server.
5. With the workstations and server plugged into ac power outlets, but powered off, check the ac ground potential difference between the server and the cluster cables that are to be connected to the server.
To do this, remove the cluster cable from one of the cluster ports on the server and measure the voltage between the server chassis and the cable shield. There must not be more than O.OlV ac between the cable shield and shared resource processor servers, or 1.0V ac between the cable shield and the workstation chassis (if a
workstation is used as a server). The resistance between server and cable shield must not exceed 1 ohm.
If the server is in the middle of the cluster, repeat step 5 for the cluster cable connected to the remaining cluster port.
CAUTION
Ground potential differences exceeding the above specifications can damage electronic components and may result in erratic cluster performance.
Installing a Daisy-Chain Cluster
6. If the server is located at one end of the cluster, connect the cluster cable to one of the RS-422 or RS-485 ports on the server, and install a terminator on the other port (make sure the terminator impedance matches the cable impedance). It makes no difference which port is used for the cable and which is used for the terminator. (See Figure 3-4.)
Figure 3-4. Connecting a Cluster Cable and Terminator If the cluster is configured with the server in the middle of the cluster, connect a cluster cable to each of the RS-422 or RS-485 ports (see Figure 3-5).
Installing a Daisy-Chain Cluster
Figure 3-5. Connecting Cluster Cables
Connecting a Workstation to the Cluster To connect a workstation,
1. Install the workstation as directed by the appropriate hardware installation guide.
2. Install the operating system and other required software (see the CTOS System Administration Guide).
3. Make sure that the workstation can support the cluster speed set at the server. (Workstations automatically use the cluster speed set at the server if they can support that speed).
4. Connect the cluster cables to the workstations and to the server, but do not power on the workstations or server.
5. With the workstations and server plugged into ac power outlets, but powered off, check the ac ground potential difference between the workstation and the cluster cables that are to be connected to the workstation.
Installing a Daisy-Chain Cluster
To do this, remove the cluster cable from one of the cluster ports on the workstation and measure the voltage between the workstation chassis and the cable shield. There must not be more than 1.0V ac . between the cable shield and the workstation chassis. The
resis-tance between workstation and cable shield must not exceed 1 ohm.
If the workstation is not at the end of the cluster, repeat step 5 for the cluster cable connected to the remaining cluster port.
CAUTION
Ground potential differences exceeding the above specifications can damage electronic components and may result in erratic cluster performance.
6. If the workstation is located at one end of the cluster, connect the cluster cable to one of the RS-422 or RS-485 ports on the workstation, and install a terminator on the other port. Make sure the terminator impedance matches the cable impedance. It makes no difference which port is used for the cable and which is used for the terminator.
(See Figure 3-4 above.)
If the workstation is not at the end of the cluster, connect a cluster cable to each of the RS-422 or RS-485 ports (see Figure 3-5 above).
Connecting a PC to the Cluster To connect a PC,
1. Install a ClusterCard adapter in the PC as directed by the ClusterCard installation guide. (See Section 2 for a list of the ClusterCards available.)
Note: All ClusterCards support a cluster speed of 1.8 Mbps. However, if you want to use a cluster speed of 3.7 Mbps, you must use an AT-bus ClusterCard installed in an 80386-based (or B0486-based) PC running at 20 MHz or faster.
2. Install the ClusterShare software in the PC and in the cluster server (see the ClusterShare Administrator's Guide).
Installing a Daisy-Chain Cluster
3. Connect the cluster cables to the workstations, to the server, and to the PC but do not power on the workstations, server, or PC.
4. With the workstations, server, and PC plugged into ac power outlets, but powered off, check the ac ground potential difference between the PC and the cluster cables that are to be connected to the PC.
To do this, remove the cluster cable from one of the cluster ports on the PC and measure the voltage between the PC chassis and the cable shield. There must not be more than 1.0V ac between the cable shield and the PC chassis. The resistance between PC and cable shield must not exceed 1 ohm.
If the PC is not at the end of the cluster, repeat step 4 for the cluster cable connected to the remaining cluster port.
CAUTION
Ground potential differences exceeding the above specifications can damage electronic components and may result in erratic cluster performance.
5. If the PC has an AT -bus ClusterCard, and the PC is at the end of a cluster, connect one DB9-RJ45 adapter cable to the either of the two ClusterCard ports (see Figure 3-6). Connect a terminator to the remaining port.
Note: An RJ45 terminator is available for 100 ohm cables. If the cluster has 140 ohm cable, you must install a second DB9-RJ45 adapter in the ClusterCard and plug a 140 ohm terminator into the adapter.
Installing a Daisy-Chain Cluster
Cluster
Card Cluster
Coble
To Cluster Workstation
Terminator
Figure 3-6. Installing a DB9-RJ45 Adapter and Terminator Adopter Coble
2702.3-6
6. If the PC has an AT-bus ClusterCard, and is in the middle of a cluster, connect two DB9-RJ45 adapter cables to the ClusterCard.
Then connect the cluster cables to the adapter cables. (See Figure 3-7.)
Installing a Daisy-Chain Cluster
Adopter Cobles 2702.3-7 Figure 3-7. Installing two DB9-RJ45 Cables
7. If the PC has an XT -bus ClusterCard, and is at the end of a cluster, connect the cluster cable to either of the RS-422 or RS-485 ports on the ClusterCard, and install a terminator on the remaining port.
Make sure the terminator impedance matches the cable impedance.
If the PC is in the middle of the cluster, connect a cluster cable to each of the RS-422 or RS-485 ports on the ClusterCard.