DB2 packets

All communication between DB2 clients and servers is done through discrete packets. Request packets are sent by clients, response packets are sent by DB2 servers, usually (but not always) in response to requests.

DB2 uses the DRDA v5 protocol, which is fairly complex. Gallium Data supports the full protocol, but gives detailed access only to the packets that are relevant to common requests and responses.

The full DRDA specification is a bit daunting -- it is comprised of three volumes, totaling about 1,500 pages. It is available from the The Open Group:

• DRDA V5 volume 1

• DRDA V5 volume 2

• DRDA V5 volume 3

Thankfully, you will typically not need to know any of this, as Gallium Data exposes requests and responses at a fairly high level. 

However, if you are familiar with DRDA, you can use generic JavaScript filters to intercept (and potentially modify) any packet. 

Keep in mind, however, that many packets are part of a complex dialog (especially when a result set is being sent back from the server), therefore many packets are not available individually. The packets documented here are treated individually and can be intercepted and potentially modified by filters.

Packet types

Parameters

The following parameters are used by various packets:

• PKGNAMCSN: refers to a specific query