IBM PureData System for Analytics, Version 7.1

Configuring MTU to enable jumbo frames

You can customize your IBM® Netezza® Platform Development Software system so that it can take advantage of the Ethernet jumbo frames.

When processing SQL queries, large volumes of data are sent between the IBM Netezza Platform Development Software virtual machines using the internal network.

To enable Jumbo Frames, you require hardware that supports changing the Maximum Transmission Unit (MTU) to 9000. That includes network adapters and switches that are used to build the IBM Netezza Platform Development Software internal network.

Follow these steps to enable jumbo frames:

In vSphere configuration for internal IBM Netezza Platform Development Software network (Distributed or Standard Switch), set MTU to 9000.
In NPS® virtual machine, edit the file /etc/sysconfig/network-scripts/ifcfg-eth1 and add the following line:
```
MTU=9000
```
As root, run the following command:
```
ifconfig eth1 mtu 9000
```
Run these commands to restart NPS:
```
nzstop
nzstart
```

Note: If the internal network is based on vSphere Standard Switched, you must change the MTU value on all ESXi nodes that are connected to this network.