IBM WebSphere Application Server Network setup

The IBM WebSphere Application Server (WAS) server and database server LPAR-to-LPAR communication is set up with IBM® System z® HiperSockets™.

See also DB2 database server network setup. The HiperSockets frame size is set to the same size as for the database server, which allows a TCP/IP MTU size of 8192 for the HiperSockets connection.

Sample command: lsqeth for the HiperSockets device:

# lsqeth hsi0 
Device name                  : hsi0                
--------------------------------------------- 
        card_type            : HiperSockets 
        cdev0                : 0.0.8000 
        cdev1                : 0.0.8001 
        cdev2                : 0.0.8002 
        chpid                : FB 
        online               : 1 
        portname             : no portname required 
        portno               : 0 
        route4               : no 
        route6               : no 
        checksumming         : sw checksumming 
        state                : UP (LAN ONLINE) 
        priority_queueing    : always queue 2 
        fake_broadcast       : 0 
        buffer_count         : 128 
        layer2               : 0 
        large_send           : no 
        isolation            : none 
        sniffer              : 0

Fine tune the HiperSockets device as follows:

• Increase the number of buffers for inbound traffic to 128 (default is 64) at /etc/udev/rules.d/51-qeth-0.0.8000.rules
• Add the following line:

  ACTION==”add“, SUBSYSTEM==”ccwgroup“, KERNEL==”0.0.8000“, ATTR{buffer_count}=”128“

The network connection between the client system and the application server is based on 10 GbE hardware for both sides. On the client system it is a 10 GbE network card and for the application server it is a 10 GbE OSA-Express3 feature. This allows a network connection at 10 Gigabits/second link speed.

Sample command: lsqeth for the OSA-Express3 device

# lsqeth eth1 
Device name                  : eth1                
--------------------------------------------- 
        card_type            : OSD_10GIG 
        cdev0                : 0.0.2100 
        cdev1                : 0.0.2101 
        cdev2                : 0.0.2102 
        chpid                : 80 
        online               : 1 
        portname             : osaport 
        portno               : 0 
        route4               : no 
        route6               : no 
        checksumming         : hw checksumming 
        state                : UP (LAN ONLINE) 
        priority_queueing    : always queue 2 
        fake_broadcast       : 0 
        buffer_count         : 128 
        layer2               : 0 
        large_send           : no 
        isolation            : none 
        sniffer              : 0

The following OSA device driver tuning is applied for the 10 GbE OSA device:

• Increase the number of buffers for inbound traffic to 128 (default is 64) at /etc/udev/rules.d/51-qeth-0.0.2100.rules
• Add the following line:

  ACTION==”add“, SUBSYSTEM==”ccwgroup“, KERNEL==”0.0.2100“, ATTR{buffer_count}=”128“ 

• Enable hardware checksumming on the OSA device at

  /etc/udev/rules.d/51-qeth-0.0.2100.rules

• Add the following line:

  ACTION==”add“, SUBSYSTEM==”ccwgroup“, KERNEL==”0.0.2100“, ATTR{checksumming}="hw_checksumming"

For details about IBM Linux™ for System z network tuning see:

https://www.ibm.com/docs/en/linux-on-systems?topic=recommendations-network-performance-tuning