From time to time while trying to connect to SA11 Server I receive the
following error:
"Connection error: Found server but communication error occurred".

At this time server seems to be not respond(hang). At that time I can
not connect to server either
- throw odbc
- Sybase Central .
- dbping

Usually the problem lasts for several minutes, but sometimes it can take
more than 20 minutes.

I found similar question in 2005 by Breck
http://groups.google.ru/group/sybase...935ac46cad67e4

but did not find any clues why it happens and how to prevent this.

Some info:
- SA 11.0.1.2308
- license type (per processor). Max # connections 32766 (as reported by
Sybase Central - Overview)
- usual number of concurrent connection ~50-100


Any suggestions?

Andrei

Hi Andrei,

Andrei Iliev wrote:
This is usually given any time you can UDP broadcast / use the sasrv.ini
cache to locate a server, but fail to connect over the TCP port.

- Can you make a local connection to the server not over TCP/IP? (i.e.
over shared memory?)

- What is the database server doing during this time? Are there any
external events that happen around this such as backups, or...? Is there
anything logged in the System Event viewer that may provide a clue?

- What's your database server start-line?

- Can you post a database console log (-z -o), or enable request level
logging during this time? (-zr SQL+HOSTVARS -zo rll.txt)

- Can you post the output of dbping?

Alternatively, opening a technical support case and using our process
tools to figure out what's happening during these specific instances may
also help.

Regards,

--
Jeff Albion, Sybase iAnywhere

iAnywhere Developer Community :
http://www.sybase.com/developer/libr...ere-techcorner
iAnywhere Documentation : http://www.ianywhere.com/developer/product_manuals
SQL Anywhere Patches and EBFs :
http://downloads.sybase.com/swd/summ...&timeframe =0
Report a Bug/Open a Case : http://case-express.sybase.com/cx/

Thanks Jeff,

No. At that time i can not connect to the server even locally.


No.

No.
-n mydb
-x tcpip{port=49162}
-o E:\mydb\db\logs.txt
-oe E:\mydb\db\logs_e.txt
E:\mydb\db\mydb.db -n mydb

Ok. I'll add the options.

I'll do it next time when it happens.


Jeff Albion [Sybase iAnywhere] wrote:

Output of dbping (running locally on the DB-server) :

SQL Anywhere Server Ping Utility Version 11.0.1.2308
Attempting to connect using:
UID=company;PWD=********;DBN=mydb;ENG=mydb;ASTOP=Y ES;DSN=mydb;INT=NO;DBG=NO;DMRF=NO;LINKS='SharedMem ory,TCPIP{host=xxx.xx.xx.226;port=49162}';COMP=No
Attempting to connect to a running server...
Trying to start SharedMemory link ...
SharedMemory link started successfully
Attempting SharedMemory connection (no sasrv.ini cached address)
Connected to server over SharedMemory
Communication function sconn::receive code 3
Communication function ApplicationConnect code 3
Cannot connect to server
Ping server failed -- Connection error: Found server but communication
error occurred.

Jeff Albion [Sybase iAnywhere] wrote:

This indicates that the server was found by the client, but it timed out
while waiting for a packet. This should (almost) never happen with
shared memory, so the server must be in some weird state. Can you add
"-z -ot server.out" to the server's command line and see if there are
any error messages in the server.out file?

Graeme Perrow
Senior Software Developer
gperrow _at_ ianywhere _dot_ com
Sybase iAnywhere Engineering

SQL Anywhere Developer Community
http://www.sybase.com/developer/libr...ere-techcorner
SQL Anywhere Blog Center
http://www.sybase.com/sqlanyblogs


Andrei Iliev wrote:

Graeme Perrow [Sybase iAnywhere] wrote:
Only message like:
TCP/IP: Received connection request from xxx.xxx.xxx.xxx:xxxx.
I. Connection from xxx.xxx.xxx.xxx:xxxxx assigned connection ID nnnn

================================================== ========
I. 10/08 02:46:50. Connection ID 3422: NCHAR character set changed to
"UTF-8"
I. 10/08 02:46:50. TCP/IP: Received connection request from
xxx.xxx.xxx.244:34233.
I. 10/08 02:46:50. Connection from xxx.xxx.xxx.244:34233 assigned
connection ID 3423
I. 10/08 02:46:50. Connection ID 3421: "company" disconnected from
database "brass"
I. 10/08 02:46:50. Connection ID 3423: "company" connected to database
"brass" from SQL Anywhere 11.0.1 (2308) client over TCPIP
I. 10/08 02:46:50. Connection ID 3423: AppInfo is
IP=xxx.xxx.xxx.244;HOST=WEBxxx;OSUSER=Administrato r;OS='Windows 2003
Build 3790 Service Pack
2';EXE=C:\user\xxx\run\xxx\xxx.exe;PID=0x1558;THRE AD=0xa34;VERSION=11.0.1.2308;API=ODBC;TIMEZONEADJU STMENT=240
I. 10/08 02:46:50. Connection ID 3423: Server character set conversion
is enabled, but not required
using character set "windows-1251"
I. 10/08 02:46:50. TCP/IP: Received connection request from
xxx.xxx.xxx.244:34234.
I. 10/08 02:46:50. Connection from xxx.xxx.xxx.244:34234 assigned
connection ID 3424
=================================Problem begins======================
I. 10/08 02:46:50. TCP/IP: Received connection request from
xxx.xxx.xxx.241:4092.
I. 10/08 02:46:50. Connection from xxx.xxx.xxx.241:4092 assigned
connection ID 3425
I. 10/08 02:46:52. TCP/IP: Received connection request from
xxx.xxx.xxx.244:34235.
I. 10/08 02:46:52. Connection from xxx.xxx.xxx.244:34235 assigned
connection ID 3426
I. 10/08 02:46:52. TCP/IP: Received connection request from
xxx.xxx.xxx.242:1673.
=======================and so on ==================================