Thanks Paul for your information. One thing I don't understand is the difference of the MQ PING and the usual PING. Usually those MTU will affect the usuall "ping -l xxx" as well. So I just don't know why the usual PING -l 1500 xx works but not MQ PING Chl datalen(1500). That's the thing that network people keep saying no problem because they don't care my MQ PING as their PING works.... So I have to dig out all information to prove they have to do something.
Cheers, Ian On 7/26/05, Paul Clarke <[EMAIL PROTECTED]> wrote: > 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 > 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
