DB Studio cannot connect to host localhost to register user management

[peter_kueppers]

Hello,

I installed MaxDB Database Studio (Version: 7.7.06.09) on Linux (openSUSE 11.1).

On login I get three errors:

1. Connect to UMDB not possible. Try to use/create local default user management.

com.sap.dbtech.jdbc.exceptions.JDBCDriverException: Cannot connect to jdbc:sapdb://server.linux.site/.UMDB [Cannot connect to host localhost:7210 [Verbindungsaufbau abgelehnt], -813.].

2. Recreation default user management failed.

com.sap.dbtech.jdbc.exceptions.JDBCDriverException: Cannot connect to jdbc:sapdb://server.linux.site/.UMDB [Cannot connect to host localhost:7210 [Verbindungsaufbau abgelehnt], -813.].

3. Connect to user management failed.

com.sap.dbtech.jdbc.exceptions.JDBCDriverException: Cannot connect to jdbc:sapdb://server.linux.site/.UMDB [Cannot connect to host localhost:7210 [Verbindungsaufbau abgelehnt], -813.].

I suppose, it has something to do with the network configuration.

Window->Preferences->User Management 'Database node' = 'localhost'.

IPv6 is active on the server and /etc/hosts contains:

::1 localhost ipv6-localhost ipv6-loopback

127.0.0.2 server.linux.site server

127.0.0.1 nil

(and more...)

The vserver is actice (at localhost 7210).

All other network related things work fine on the Server.

I tried several solutions:

1. When I change 'nil' to 'localhost' in /etc/hosts, I get the same error as above.

2. When I change 'localhost' to '127.0.0.1' in 'Database node', Check with 'Reset User Management' and Register the .UMDB Database, I get the error:

Connect failed.

com.sap.dbtech.jdbc.exceptions.JDBCDriverException: Cannot connect to jdbc:sapdb://server.linux.site/.UMDB [Cannot connect to host localhost:7210 [Verbindungsaufbau abgelehnt], -813.].

3. When I change 'localhost' to 'nil' in 'Database node' and register manually to the .UMDB Databse, I get the message:

User management database successfull registered.

Refresh your <Local> server to see the user management database.

But I don't know how to refresh the server (vserver, xserver?) and I can't see any database.

And when I restart the MaxDB Database Studio, I have again 'localhost' in 'Database node' (although 'nil' was saved in /var/opt/sdb/data/app/dbstd/um.properties before) and same problems as above.

Any idea for a solution?

Cheers

Peter

Edited by: Peter Kueppers on Apr 1, 2009 9:36 PM

[Melanie]

Hello Peter,

as which user did you try to start Database Studio? Try to use root or at least a user who is member of group sdba.

Regards,

Melanie

[peter_kueppers]

Hello Melanie,

thanks for the answer.

The user is a meber of sdba group.

I did not try root, since root is a 'bad user to use'

Cheers

Peter

[Former Member]

Hello,

can you check if your x_server is running?

Please map localhost to 127.0.0.1 in /etc/hosts.

Best Regards

Wolfgang

[peter_kueppers]

Hello Wolfgang,

I can see a process 'v_server' running (hope that's x_server?).

When I map 127.0.0.1 with localhost, I get the same error.

Thanks

Peter

[Former Member]

Hello,

can you connect to the .UMDB using the dbmcli?

Best Regards

Wolfgang

[peter_kueppers]

Hello Wolfgang,

thanks for your answers.

Yes, it's possible to connect to the UMDB using the dbmcli.

I've other strange effects:

1. When I kill the vserver process (after I used solution 3), close the Database Studio and reopen it, bingo I can see and access the UMDB (another vserver starts automatically in the background).

But there are still two processes running on user sdb in the backgrpoung when I kill the vserver: kernel and dbmsrv.

When I kill all sdb related processes and start Database Studio again, I've the effect that 'Database node' changes automatically from 'nil' to 'localhost (in /var/opt/sdb/data/app/dbstd/um.properties) and I've the same problems as above.

2. When I change network from IPv6 to IPv4 (and reboot the server), bingo everything works fine!

Maybe there is ab bug in the user management of Database Studio in association with IPv6?

Cheers

Peter

[Former Member]

Hello,

• The vserver is the "listener" for MaxDB. When you kill it the kernel keeps running.

• I think that empty values in um.properties are set to a "valid" entry by Database Studio. I would recommend you enter 127.0.0.1 in the um.properties.

• Database Studio is Java/JDBC based. We do not have a special implementation for IPv6.

• Did step 1) or step 2) resolve your problems? Or both?

Best Regards

Wolfgang

[peter_kueppers]

Hello Wolfgang,

neither solution 1 nor 2 works for me (see above).

It's quite strange, that it's possible to access UMDB under IPv4 but not under IPv6. But I'm not an expert on this.

While searching for the processes related to sdb, I found out that there are many steps (an so processes) which are performed during registering the UMDB (e.g. dbmcli with different commands).

I'll try to 'collect' them (maybe via acct) and I'll execute them in a terminal step by step to see the logging.

But this will take some time...

Cheers

Peter

[Former Member]

Hello,

MaxDB does not support IPv6. Please change your system to IPv4.

Best Regards

Wolfgang

[peter_kueppers]

Hello Wolfgang,

in response of 'MaxDB does not support IPv6' I would like to say yes and no.

As I found with my testing, it's possible to run the MaxDB Database Studio with the described 'workaround' (solution 3, kill vserver and restart Database Studio). And it's possible to administrate a remote MaxDB for a SAP Netweaver with this tool!

I've found in the internet a document with the same problems I had (http://dev.mysql.com/tech-resources/articles/UnitedDrugs-UserReport-2006.pdf) and a note from SAP:

Note from the SAP Development Team: Actually, static IPs are not required, we recommend that

domain/host names are used. Unfortunately by setting defaults to u2018127.0.0.1u2019 instead of u2018localhostu2019, it was

suggested that IPs are needed. This was done, since some linux flavors resolve u2018localhostu2019 to an IPv6 IP (notably SuSE) . Such IPs are not understood by MaxDBu2019s x_server and (at the time by many other applications as well). We will set the default back to u2018localhostu2019 and address the IPv6 problem in the documentation.

From my tests I'm quite shure that MaxDB works on an IPv6 network, but the problem is to connect (via x_server) to the database. And I'm quite shure, that it depends on the linux distribution whether the connection (in this case cooperation between IPv4 and IPv6) works (out of the box) or not.

I know that the use of IPv6 is only very restricted at the moment and buggy with some applications, but it's upcoming. There is a discussion, that some of the investment in this economical crisis will go in an IPv6 network in Europe. So it would be good to have a solution here.

Cheers

Peter

Edited by: Peter Kueppers on Apr 5, 2009 10:58 PM