Communication Link Failure?

Hai,

Iam using VC++ application to connect remote database(MSSQL) through network.

Everything works fine, if the network connection is active. If the network breaks and resumes, the application throws "Communication Link Failure" and do not get connected even after the network is resumed.

Client :

* Windows 2000 Professional

* MDAC 2.5

* VC++, using framework- CRecordset to access database

* PEER to PEER network configuration

* DSN through ODBC

Server :

* Windows 2000 Professional

* MDAC 2.8

* MSSQL Server

how to resume the database connection ?

Any one help me?

Thanks in advance,

If an existing connection fails due to broken network connectivity the client application must open a new connection to the server.

Does the new connection fail as well? If so, what is the full error message text?

|||

No..if the application is restarted the connection resumes..

Do i have to make a new connection after the broken network connectivity? Is there any other solution without reconnecting?

|||

Yes, you have to make a new connection after the broken network connectivity.

|||Thank you..

Communication link failure

Hello
We are using Access 2003 (SP2) to access a remote SQL 2000 database,
using ODBC with MDAC 2.8
This is an intermittent problem and it occurs on all the clients
(mostly winXP Pro)
The problem is that from time to time, the ODBC connection fails and we
get one of several errors:
ODBC--call failed
[Microsoft][ODBC SQL Server Driver][DBNETLIB]ConnectionWrite (se
nd()).
(#10054) [Microsoft][ODBC SQL Server Driver][DBNETLIB].General n
etwork
error. Check your network documentation.
or
ODBC--call failed
[Microsoft][ODBC SQL Server Driver][Communications link failure
(0#)
We know that sometimes there are network problems (we connect accross a
CDMA mobile network) - the cause of this is not in question.....
Retrying the operation immediatly returns the same error but when we
close and re-open access and re-run the operation, and then it will
work straight away.
So, it seems that the driver enters a "failure state" - which is reset
when access is closed and re-opened.
I desperately need to find a way to "reset' the driver when this
happens so that we don't have to keep restarting access.
Anyway help would be much appreciated.
thanks !
RobHow you address it depends partly on how you are access the
SQL 2000 database, what this operation does that you are
retrying.
Just a guess but if this is linked tables, then you should
create some VBA function in Access to relink (not refresh)
the tables in code. Then you can try executing this function
instead.
-Sue
On 16 May 2006 03:17:49 -0700, saikosounds@.gmail.com wrote:

>Hello
>We are using Access 2003 (SP2) to access a remote SQL 2000 database,
>using ODBC with MDAC 2.8
>This is an intermittent problem and it occurs on all the clients
>(mostly winXP Pro)
>The problem is that from time to time, the ODBC connection fails and we
>get one of several errors:
>ODBC--call failed
>[Microsoft][ODBC SQL Server Driver][DBNETLIB]ConnectionWrite (s
end()).
>(#10054) [Microsoft][ODBC SQL Server Driver][DBNETLIB].General
network
>error. Check your network documentation.
>or
>ODBC--call failed
>[Microsoft][ODBC SQL Server Driver][Communications link failure
(0#)
>We know that sometimes there are network problems (we connect accross a
>CDMA mobile network) - the cause of this is not in question.....
>Retrying the operation immediatly returns the same error but when we
>close and re-open access and re-run the operation, and then it will
>work straight away.
>So, it seems that the driver enters a "failure state" - which is reset
>when access is closed and re-opened.
>I desperately need to find a way to "reset' the driver when this
>happens so that we don't have to keep restarting access.
>Anyway help would be much appreciated.
>thanks !
>Rob|||Yes, the tables are linked, but there are lots and lots of tables !
Relinking then through code takes longer than re-starting Access ! !|||Then try a refresh instead - I'm not sure if a restart does
this or not. The issue is more of one related to Access
linked tables so you may want to post this in an Access
newsgroup.
-Sue
On 16 May 2006 17:08:29 -0700, saikosounds@.gmail.com wrote:

>Yes, the tables are linked, but there are lots and lots of tables !
>Relinking then through code takes longer than re-starting Access ! !|||You either need to fix the network connection, relink the tables, or automat
e
a restart. In Access, you can actually reopen the database through VBA, if
I
remember correctly.
--
MeanOldDBA
derrickleggett@.hotmail.com
http://weblogs.sqlteam.com/derrickl
When life gives you a lemon, fire the DBA.
"Sue Hoegemeier" wrote:

> Then try a refresh instead - I'm not sure if a restart does
> this or not. The issue is more of one related to Access
> linked tables so you may want to post this in an Access
> newsgroup.
> -Sue
> On 16 May 2006 17:08:29 -0700, saikosounds@.gmail.com wrote:
>
>

Communicating with a SQL Server installed on a remote machine using a web service

I have SQL Server 2005 express installed on my machine, and I was wondering if there is any way to have an asp.net 2.0 web service hosted by a different company be able to send sql commands to the sql server on my machine.

Yes.

It would require that you make your computer somewhat vulnerable to the internet.

You will have to open a port in the firewall.

You will have to deal with Web Services security issues or all kinds of folks 'could' be sending commands to your SQL Server. And if your security isn't 'irontight', one of those commands could even be "FORMAT C:".

So my point is yes, it can be done, I want you to understand that there are a lot of steps necessary to 'do it right'.

|||Thank you for your help with this. I think for now I will hold off on this until I can find time to research the security issues much more thouroughly.