Admin Alert: New TCP/IP Functions to Check Out When Upgrading to i5/OS V5
October 26, 2005 Joe Hertvik
As shops upgrade old AS/400 and iSeries systems to modern i5 machines running i5/OS V5R3, many administrators are discovering their newer operating systems provide more goodies than the systems they left behind. This week, I reviewed some of the newer TCP/IP features that IBM added to the system starting in i5/OS V5R1. If you are upgrading your old AS/400 gear this year, here are some of the new TCP/IP features you may now be able to take advantage of.
- Checking your i5/OS TCP/IP routing by using TRACEROUTE. Long available in most other networked operating systems, Trace TCP/IP Route (TRACEROUTE) only recently arrived in i5/OS with V5R1. i5 TRACEROUTE has the usual features of its non-i5/OS counterparts. But it also contains a few i5/OS specific items, such as the ability to send either regular or verbose messages to the calling job’s joblog and the really cool ability to send results to an i5/OS data queue, which can easily be read by both i5/OS and non-i5/OS applications. You can also specify that the probes should go out from any IP interface on the system (*ANY) or from a specific local interface.
- End i5/OS TCP/IP abnormally. Similar to the End Job Abnormal command (ENDJOBABN), which ends a job that cannot be ended by any other means, the V5RX End TCP/IP Abnormal command (ENDTCPABN) forces i5/OS TCP/IP processing to abnormally end if the regular End TCP command (ENDTCP) cannot do the job. But like ENDJOBABN, there are specific rules for when ENDTCPABN should be used:
* Before you can run ENDTCPABN, you must first run ENDTCP with the option to end all TCP/IP processing immediately. This is done through the following ENDTCP command:
* After running ENDTCP, i5/OS will prevent you from running ENDTCPABN for 10 minutes. This is a conscious design point to provide ENDTCP with enough time to normally end before forcing it down with ENDTCPABN.
* Once ENDTCPABN ends TCP/IP processing, you will probably be able to restart TCP/IP again without IPLing the system. And, unlike the ENDJOBABN command, using ENDTCPABN will not mark your last system IPL as abnormal so you should be able to complete a normal system reset the next time you IPL.
- View jobs associated with a particular local TCP/IP port through NETSTAT or iSeries Navigator. If you’re wondering which jobs are using a particular TCP/IP port, you can now look at and work with any jobs associated with a particular connection and port. This ability can be used on either the green screen through the Work with TCP/IP Network Stats command (NETSTAT) on in iSeries Navigator. In NETSTAT, simply place an ‘8’ in front of the connection you want to view the associated jobs for. A job list will show up and you can place a ‘5’ (Work with Job) in front of each job to view that job’s information.
- Starting in V5R1, IBM added several TCP/IP performance improvements to increase throughput as well as to quickly establish and service the thousands of connections you might experience when using an i5 box as a Web server or as a Domino box. So just upgrading to i5/OS V5RX may stabilize and improve your TCP/IP connectivity.
- IBM introduced a new network Quality of Service (QoS) server in i5/OS V5. This server enables your iSeries to function as a QoS server or client, but not as a router. QoS allows you to establish network priority and bandwidth requirements for TCP/IP applications, allowing you to smooth out network traffic and ensure that traffic flow fits your organization’s needs. For more information on i5 QoS, read the iSeries Quality of Service manual.
- IBM also added another feature that provides for the automatic update of a DNS server as new clients are added and removed from the iSeries DHCP server. This feature, called Dynamic Domain Name System (DDNS) can automatically add or remove a PTR resource record or an ‘A’ resource record to a DNS configuration. For more information on DDNS, see the IBM eServer iSeries IP Networks Dynamic redbook.
- New only with i5/OS V5R3 is an open source implementation of the Common Information Model Object Manager (CIMOM) called Pegasus. The Common Information Model (CIM) is a major component of the Web Based Enterprise Management (WBEM) initiative, and CIM provides a model for describing and accessing data across an enterprise. More information on CIM and CIMOM can be found in the iSeries Information Center, Version 5 Release 3.
Although it may seem odd to be discussing operating system enhancements three to five years after the i5/OS V5 operating system was first released, it is important to remember that, because of the depreciation cycle and the fact that most organizations will not buy a new i5 box every year, many shops may just now be getting around to upgrading to the newer operating system. If you fall into that category, you might want to check out these enhancements to see how they can improve your shop’s TCP/IP performance.