Ian, I did a quick search on the Web and came up with this
http://www.cisco.com/warp/public/105/38.shtml It may be of no use but there might be something in there that would help you, Cheers, P. Paul G Clarke WebSphere Messaging Clients IBM Hursley MQSeries List <[email protected]> wrote on 26/07/2005 08:05:01: > Hi, > > Unfortunately I have a production MQ problem today!! Actually I > believe it's not a MQ problem but a network problem. However, when > messages cannot be delievered, it's a "MQ problem". > > I would like to get some advice from the list before I spent time to > get all different groups to do a trace. > > Problem details : > > Box 1 > Windows NT4 running MQ 5.3 > > Box 2 > z/OS 1.4 running MQ 5.3 > > Messages are to be sent from NT to z/os one way only. No changes on > MQ at both end. When problem happen, the channel status at QM1 shows > running. However, when look at the detail status , it stops at the 25 > messages. That is for example when the xmitq got 100 messages, when I > started the channel and display qlocal(xmit queue), it shows 75 > messages. If I display chs, it shows msg(25) and curmsgs(26). On the > mainframe end, the rcvr shows running as well (with msg 0) but after > around 5 minutes, the adopt Mca kicks in and reestablish the > connection. On the Window end, the error log shows a TCP/IP error > 10054 (connection forcily closed by remote host). Usually that's due > to network problem. > > I've tried to change the batchsz to 1 with no luck except the ql(xmit) > becomes 99 and the chs all with MSG become 1. All other errors message > are the same. > > I then tried the PING CHANNEL and it worked. I then dump the xmitq > messages and found that the messages around 1300-1500 bytes so I use > PING CHANNEL with DATALEN(1500). This time....." AMQ9208..error > receiving from host..." in runmqsc. > > I then do a command prompt PING without problem. I do PING again with > length 1500 and 10000 and still ok ( response is fast too). Then I do > a TSO PING from z/OS wiith length 1500 and 10000 as well without > problem. > > As usual, contact network team for the problem and they usually come > back with a ping statistics saying "no problem' on network at all > regardless what -l they used in ping. > > So the problem come back to me. I tried redefine another channel but > with same symptom. As I strongly believe it's a network problem > between the 2 sites, I use a another qmgr in a UNIX box as a middle > man. So I send those messages from NT box to the middleman UNIX qmgr > and then to the mainframe qmgr. Hurray! Now everything works fine and > message all gone through. So..I believe nothing wrong the the qmgr on > NT and z/OS. > > As it's just a temporary solution, now I have to find out the root > cause. I tried the MQ PING again to some other boxes from the NT box > without problem of data length 1500. I tried multiple time to the z/OS > and figured out problem happen when DATALEN is bigger than or equal to > 1427. > > Anyone got any idea? I know ethernet size is 1500 so it looks like > something with MTU size but it should also affect command prompt ping > as well? What 's the difference between the command prompt ping and > the MQ ping except MQ go through the MQ port and verify the channel > name? > > Thanks in advance, > > Ian > > Instructions for managing your mailing list subscription are provided in > the Listserv General Users Guide available at http://www.lsoft.com > Archive: http://listserv.meduniwien.ac.at/archives/mqser-l.html Instructions for managing your mailing list subscription are provided in the Listserv General Users Guide available at http://www.lsoft.com Archive: http://listserv.meduniwien.ac.at/archives/mqser-l.html
