Solved

AS400 Communication Problems

Posted on 2004-08-30
37
806 Views
Last Modified: 2008-03-10
Hi Everyone

I have a huge problem which started recently.

I have a 170 running V4R5. The problem im having is that I can connect to the system using Client Access but about 10 minutes later, the sessions die out. I can ping fine, but the actual telnet sessions do not connect. No communications can connect at all.

To get the system back up I have to end tcp and start it again or it also comes back when I do a strtcpsvr *all

When I look at the netstat screen all previously open sessions are still sitting there as if they were still active.

I do not see any error messages in qsysopr nor do I see any joblogs in the qezjoblog.

There have been no changes to the system, and the system has been working fine for years.

This is a very important matter, as this is our target system for mirroring, and there is a hurricane in our sites....so any any any help is appreciated...I will be checking this thread constantly to answer any questions!

0
Comment
Question by:DavidASolis
  • 16
  • 15
  • 3
  • +1
37 Comments
 
LVL 6

Expert Comment

by:dedy_djajapermana
ID: 11931319
Hi,

Check the joblog of QTVTELNET job, there maybe more than one. QTVTELNET is the job handling telnet connection.
WRKJOB QTVTELNET
0
 
LVL 6

Expert Comment

by:dedy_djajapermana
ID: 11931358
I think the problem is with TELNET job, try to restart TELNET server only instead of restarting entire TCP services when the problem arise (to prove that the problem is with TELNET server).
ENDTCPSVR *TELNET
STRTCPSVR *TELNET
0
 
LVL 13

Expert Comment

by:samic400
ID: 11931616
Are the telnet sessions being disconnected at all? I would think if a job has been disconnected, it might still be active when you check out netstat.

Check out QINACTITV to see if possibly people are being disconnected after whatever the system value is set at.

Probably not related, but I figured I'd throw it out there.

In addition to the above steps in the previous posts, I would think you would need to start up the Client Access Host Servers too - STRHOSTSVR *ALL

0
 

Author Comment

by:DavidASolis
ID: 11932129
It looks like my problem is related to the Telnet server. I ended and started that and was able to connect. Problem is there are no error messages at that job when I end it.   Any ideas??
0
 

Author Comment

by:DavidASolis
ID: 11932503
The host servers all have been started. I tried FTPing too while this was happening and that does not work either, but when I end the telnet server and restart it...it all works again.
0
 

Author Comment

by:DavidASolis
ID: 11932510
Also the QINACTITV is set to *NONE
0
 
LVL 6

Expert Comment

by:dedy_djajapermana
ID: 11932638
checked the joblog of QTVTELNET
WRKJOB QTVTELNET option 10 (if the job is still active)
WRKJOB QTVTELNET option 4 - spooled files (if the job is not active)
0
 
LVL 6

Expert Comment

by:dedy_djajapermana
ID: 11932641
?
0
 

Author Comment

by:DavidASolis
ID: 11932797
the only message that shows up is the following.... SSL socket operation received return value error -93.
0
 

Author Comment

by:DavidASolis
ID: 11933030
The odd thing is when telnet stops working from outside the machine....I try telneting from the console to the machine's loopback address and that works!

0
 
LVL 6

Expert Comment

by:dedy_djajapermana
ID: 11933058
do you use SSL for your client access?
does telnet from PC work?
windows: START, RUN, type TELNET xxx.xxx.xxx.xxx <enter>
0
 

Author Comment

by:DavidASolis
ID: 11933189
No to both questions....telnet from windows just hangs
0
 
LVL 6

Expert Comment

by:dedy_djajapermana
ID: 11933208
did you try to restart telnet server ONLY instead of restart TCP?
0
 
LVL 6

Expert Comment

by:dedy_djajapermana
ID: 11933287
if it works after restarting TELNET server only, then we can concentrate on TELNET server.
Also check QTVDEVICE joblog (Besides QTVTELNET)
0
 

Author Comment

by:DavidASolis
ID: 11933347
Yes, ive been ending and starting only the TELNET server, so thats what ive been concentrating on...I'll look at the QTVDEVICE log now...
0
 

Author Comment

by:DavidASolis
ID: 11933585
I do not get any error messages under the QTVDEVICE jobs....just acknowledges program start.

Under the QZSOSMAPD job I get the following messages...
Job 532212/QUSER/QZSOSMAPD submitted.                                  
Object changed.                                                        
Object changed.                                                        
The protocol required to support the specified address family is not  
  available at this time.                                              
Host server communications error occurred on socket() - spx family.    
0
 

Author Comment

by:DavidASolis
ID: 11936193
Anyone with other ideas??
0
 

Author Comment

by:DavidASolis
ID: 11938012
My problem seems to be exactly what this person was encountering..

http://experts-exchange.com/Programming/Programming_Platforms/AS400/Q_21046608.html

I have tried what was written in that thread but none of the accepted answers have worked
0
How to run any project with ease

Manage projects of all sizes how you want. Great for personal to-do lists, project milestones, team priorities and launch plans.
- Combine task lists, docs, spreadsheets, and chat in one
- View and edit from mobile/offline
- Cut down on emails

 

Author Comment

by:DavidASolis
ID: 11938067
The only thing I have not tried is, IPLing with a restart *no .... I do not see the reasoning behind why that would make a difference. I have however performed a full IPL and no luck.
0
 
LVL 6

Accepted Solution

by:
dedy_djajapermana earned 500 total points
ID: 11938347
hi again David,

I think the problem is not the same, yours, the interface is still active, and you can ping the IP, only the telnet service is hung.
I still feel that you should see something on the joblog...
You mentioned that you can still see the connection active from NETSTAT, eventhough your session is dead, could you try the following when the problem comes:
NETSTAT
put option 8 on the "hanging telnet connection" <enter>
put option 5 on QTVDEVICE job <enter>
put option 10, then press F10, then see at the bottom, any error?
0
 
LVL 3

Expert Comment

by:Mind_nl
ID: 11938689
when you do a DSPLOG for around the time your clients hang, can you find any jobs ending or sending an error?
0
 

Author Comment

by:DavidASolis
ID: 11942258
The only errors I see in the QTDEVICE job are messages like....
 Device QPADEV000I associated with client 172.28.46.150 port 4051 has been
   recovered.                                                            


172.28.46.150 is my IP
0
 
LVL 6

Expert Comment

by:dedy_djajapermana
ID: 11944392
nothing's seem to be close so far...
does the problem happen to multiple PC? or only to one PC? (i was thinking of possibility of duplicate PC IP address)
When you mention you can telnet to local loopback address, was it 127.0.0.1 or the network IP address?
0
 

Author Comment

by:DavidASolis
ID: 11944570
It was 127.0.0.1

It happens from any PC I try, even on the same network segment (I thought maybe a firewall or router was causing this)
0
 
LVL 6

Expert Comment

by:dedy_djajapermana
ID: 11944837
i suspect there's some corruption in the license program, that's what i can think of...
do you want to try to delete and re-install tcp/ip services licensed program?
0
 
LVL 13

Expert Comment

by:samic400
ID: 11944872
What about CUM Tape level?  Latest and greatest out there for your version and release?
0
 
LVL 6

Expert Comment

by:dedy_djajapermana
ID: 11944907
or maybe wait for other experts opinion...
0
 
LVL 6

Expert Comment

by:dedy_djajapermana
ID: 11944932
yeah, i assumed you have some CUM PTF level on both system... have you checked?
0
 

Author Comment

by:DavidASolis
ID: 11947677
CUM Levels are the same on both systems...I checked to make sure all PTFs related to Telnet were applied as well.
0
 

Author Comment

by:DavidASolis
ID: 11947688
How would I go about deleting and re-installing the tcp/ip services?
0
 
LVL 6

Expert Comment

by:dedy_djajapermana
ID: 11948455
first, make sure you have the OS installation CD, when you're ready with it:
- Go to terminal, ENDTCP *IMMED
- type GO LICPGM
- take option 12 Delete licensed program
- put option 4 on  5769TC1    *BASE   TCP/IP Connectivity Utilities for AS/400
licensed program is now deleted, you shouldn't be able to STRTCP now

install:
- option 11 from LICPGM menu
- insert the OS CD
- put option 1 on 5769TC1    *BASE   TCP/IP Connectivity Utilities for AS/400
- key in your optical drive when prompted

now you have to re-install PTF related to 5769TC1 (you can also reinstall the latest CUM PTFs)
you may want to test it before reinstall the PTF

0
 
LVL 3

Expert Comment

by:Mind_nl
ID: 11950519
hmmm re-install sounds like a windows fix... This should not be nessesary but yes it will rule out some posible causes for you... re-installing TCP/IP shouldn't take long anyways...
Also take a PC and place it as close to the AS/400 as possible: on the same switch. This will rule out all other network hardware currently in between the AS/400 and your PC...
0
 
LVL 6

Expert Comment

by:dedy_djajapermana
ID: 11950539
switch problem can be ruled out, i think, telnet from the AS/400 itself to its network adapter IP address was fail..
0
 
LVL 3

Expert Comment

by:Mind_nl
ID: 11951046
ah, sorry I must have missed that...
0
 

Author Comment

by:DavidASolis
ID: 11954297
Hey guys, would like to let you all know that I found out late last night what the problem was....

This machine is on a network in another state at our coporate headquarters...I was looking into DNS and saw that when I did an nslookup on the name of the machine DNS would return the correct address....when I reversed the nslookup to the ip address, a different machine name would show up with the same IP.

Looks like someone threw a machine onto the network with the same IP address...and either the 2 machines were conflicting with each other (which would be why I could still ping the address even though I couldnt connect) or the DNS entries were conflicting with each other when either the AS/400 refreshed its DNS cache or when the client was refreshing they got the wrong name....Im going with option 1 though.

Thanks for all your help! It was greatly appreciated!! This site is a valuable forum for people!!
0
 
LVL 6

Expert Comment

by:dedy_djajapermana
ID: 11954769
you're welcome
0

Featured Post

Maximize Your Threat Intelligence Reporting

Reporting is one of the most important and least talked about aspects of a world-class threat intelligence program. Here’s how to do it right.

Join & Write a Comment

In  today’s increasingly digital world, managed service providers (MSPs) fight for their customers’ attention, looking for ways to make them stay and purchase more services. One way to encourage that behavior is to develop a dependable brand of prod…
What is Backup? Backup software creates one or more copies of the data on your digital devices in case your original data is lost or damaged. Different backup solutions protect different kinds of data and different combinations of devices. For e…
In this seventh video of the Xpdf series, we discuss and demonstrate the PDFfonts utility, which lists all the fonts used in a PDF file. It does this via a command line interface, making it suitable for use in programs, scripts, batch files — any pl…
When you create an app prototype with Adobe XD, you can insert system screens -- sharing or Control Center, for example -- with just a few clicks. This video shows you how. You can take the full course on Experts Exchange at http://bit.ly/XDcourse.

707 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

17 Experts available now in Live!

Get 1:1 Help Now