SAP RS - The transaction log in database RSSD is almost full

What happened?
Error when trying to start SAP Replication Server.

Error Message:
E. 2020/12/14 21:39:52. ERROR #11061 GLOBAL RS(GLOBAL RS) - generic\sts\stscol.c(2631)

Check the log for error messages from RSSD.
I. 2020/12/14 21:39:52. Message from server: Message: 7415, State 1, Severity 10 -- 'The transaction log in database RS1_RSSD is almost full. Your transaction is being suspended until space is made available in the log.

Reason:
Cause of the error: The transaction lof of the RSSD database is (almost) full.

Solution:

use master

go

sp_helpdb RS1_RSSD  --a check

sp_helpdevice rssd_log --a check

disk resize name = "rssd_log", size = "1500M"

go

alter database RS1_RSSD log on rssd_log = "1500M"

go

MySQL - Find where the error log is stored

mysql> SHOW VARIABLES LIKE 'log_error’;

SAP RS: Can't connect to RS but can connect to ASE in the same server

What happened?
Can't connect to RS but can connect to ASE in the same server:

C:\SAPRS>isql64 -S RSSERVERNAME -Usa -Ppassword
CT-LIBRARY error:
        ct_connect(): user api layer: internal Client Library error: Read from the server has timed out.
CT-LIBRARY error:
        ct_connect(): network packet layer: internal net library error: Net-lib operation timed out

C:\SAPRS>isql64 -S ASESERVERNAME -Usa -Ppassword
1>

Error message:
Check in the RS log:

I. 2020/04/22 20:34:47. Check the log for error messages from RSSD.
I. 2020/04/22 20:34:47. Message from server: Message: 7412, State 2, Severity 10 -- 'Space available in the log segment has fallen critically low in database 'RS_RSSD'.  All future modifications to this database will be suspended until the log is successfully dumped and space becomes available..

Cause: 
Log space of the RSSD database (of the RS) is full.
Check it using:

sp_helpdb <RSSDNAME>
sp_helpdevice <RSSDLOGDEVICENAME>

Solution:
Add space to the RSSD log:
http://copypastenet.blogspot.com/2020/01/sap-ase-sybase-transaction-log-in.html

SAP ASE (Sybase) - write to the server log - logprint

dbcc logprint('itai test errorlog')
-- will be written with severity=0
or:

sp_addmessage 20002, 'itai test sp_addmessage with_log'
raiserror 20002
-- will be written with severity=0

or:

sp_addmessage 20002, 'itai test sp_addmessage with_log', @with_log=TRUE
raiserror 20002
-- will be written with severity=16

or with parameters:
sp_addmessage 20003, 'itai %1! sp_addmessage with parameters', @with_log=TRUE
raiserror 20003, 'parameter'
-- will be written with severity=16

WITH (TABLOCK) - Minimal logging while insert

In order to improve performance for an insert statement,

We can consider use WITH (TABLOCK) option:

INSERT INTO dbo.testItai WITH (TABLOCK) (id, NAME) SELECT ...

Whet it will do is to minimize the writes to the log.

Try it:

Run insertion statement with and without the TABLOCK and check the log:

INSERT INTO dbo.testItai (id, NAME)

SELECT TOP 5000 ABS(CHECKSUM(NEWID())) % 100,

       char(65+ ABS(CHECKSUM(NEWID())) % 26) + char(65+ ABS(CHECKSUM(NEWID())) % 26) + char(65+ ABS(CHECKSUM(NEWID())) % 26) + char(65+ ABS(CHECKSUM(NEWID())) % 26) + char(65+ ABS(CHECKSUM(NEWID())) % 26) +char(65+ ABS(CHECKSUM(NEWID())) % 26)

FROM master..sysobjects a cross join master..sysobjects b

INSERT INTO dbo.testItai WITH (TABLOCK) (id, NAME)

SELECT TOP 5000 ABS(CHECKSUM(NEWID())) % 100,

       char(65+ ABS(CHECKSUM(NEWID())) % 26) + char(65+ ABS(CHECKSUM(NEWID())) % 26) + char(65+ ABS(CHECKSUM(NEWID())) % 26) + char(65+ ABS(CHECKSUM(NEWID())) % 26) + char(65+ ABS(CHECKSUM(NEWID())) % 26) +char(65+ ABS(CHECKSUM(NEWID())) % 26)

FROM master..sysobjects a cross join master..sysobjects b 

Check the log using

select * from fn_dblog(null, null)

You will see that after the insertion without the TABLOCK 5000 records will be written in the log, and much less with the TABLOCK.

WITH (TABLOCK) has few constraints:

1. The destination table must be empty or without clustered index.

2. There is no non-clustered index on the destination table.

fn_dblog - display the log file

fn_dblog is an undocumented SQL function that display the log file.

select * from fn_dblog(null, null)

1. The first parameter is the starting log sequence number. NULL = from the first number.
2. The second parameter is the ending log sequence number. NULL = to the last number.

• Read more about Reading Transaction Log File here:

http://blog.sqlauthority.com/2014/10/15/sql-server-beginning-reading-transaction-log-file/