Dedicated Admin Console (DAC) a reserved connection on SQL Server that grants special access to system tables and can help diagnose problems
Questions tagged [dac]
23 questions
15
votes
3 answers
Is it possible to estabilish Dedicated Administrator Connection (DAC) using SSMS?
Is it possible to connect to the DAC using SSMS?
If I understand correctly, it should be possible by using "admin:" prefix before the server name, but I receive the following message:
Dedicated administrator connections are not supported via SSMS…
user6426
5
votes
1 answer
Static DAC ports for named instances
Using SQL 2016 Enterprise Edition
The default instance will listen on 1433 and the DAC port will listen on TCP 1434. SQL Browser will listen on UDP 1434. Any subsequent named instances will get a dynamically allocated port from windows in the range…
Gavin Harris
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5
votes
2 answers
Enabling admin connection on SQL Server Express to fix logon trigger
Well, luckily I got this error on my test environment. I'm so scared about this error that I disabled all logon triggers I was using on production environment.
I created the famous logon trigger, and I put a database in offline mode just to mess…
Racer SQL
- 7,004
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4
votes
1 answer
When using DAC, receiving the "[…] the maximum number of '1' dedicated administrator connections already exists" message in error log
I am about to escalate this to MS, but I thought I would try here first and see if anyone has any ideas as to how to prevent this faux error message...
When connecting to SQL Server (2016 and 2017 latest builds) with a dedicated administrator…
RelativitySQL
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4
votes
1 answer
Is it possible to connect MS SQL Server Express 2012 through DAC Connection?
Is it possible to Connect MS SQL Server 2012 Express Through DAC. After moving from SQL Server 2012 Enterprise to MS SQL Server 2012 Express, some performance problem were there. When i have checked out using this TSQL
select * from…
Md Haidar Ali Khan
- 5,967
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3
votes
2 answers
Why SQL Server Service Account connects to the DAC?
We started getting Alerts:
Could not connect because the maximum number of '1' dedicated administrator connections already exists. Before a new connection can be made, the existing dedicated administrator connection must be dropped, either by…
VitalicJJ
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3
votes
1 answer
How do we find who used Dedicated Admin Connection
Is there any way to find who used Dedicated Admin Connection?
Not active connection but the previous one which is already closed?
Santhoshkumar KB
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3
votes
1 answer
How do I know what requires DAC?
Playing around with SQL Server, I came across a semi-cryptic error. Essentially, I only need to log into DAC. Is there any general advice for when DAC is needed? How do I know I need it to access sys.sysobjvalues without googling for the error…
NO WAR WITH RUSSIA
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3
votes
1 answer
How do I log into the Dedicated Admin Console (DAC) on Linux?
sqlcmd is documented to have,
Login-Related Options
-A
Logs in to SQL Server with a Dedicated Administrator Connection (DAC). This kind of connection is used to troubleshoot a server. This will only work with server computers that support DAC. If…
NO WAR WITH RUSSIA
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2
votes
2 answers
DAC connection error
I'm having a problem connecting using my dedicated admin connection in SQL Server 2014. I just wanted to test it out.
I have DAC enabled in sp_configure. I have performed RECONFIGURE.
I have prefixed my connection string with ADMIN: in SSMS Connect…
user3469285
- 651
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2
votes
0 answers
Severity 20 Error upon disconnecting Dedicated Administrator Connection
Starting working with Dedicated Administrator Connections on SQL Server 2008 R2 servers. All is working fine (once port 1434 was opened), but am getting severity 20 errors when I disconnect the admin connection.
From within SSMS, I am opening a new…
CJ Gregory
- 21
- 2
2
votes
1 answer
Azure SQL Database - dedicated administrator connection (DAC)
If you check the setting in any of your Azure SQL databases, you will see that the value_in_use column value is zero for Remote admin connections. Meaning ‘Remote admin connections’ are not allowed from remote clients. There is no way to change that…
SqlWorldWide
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2
votes
0 answers
DAC silently swallows tokenization errors in sp_msforeachdb
This morning I hopped on the DAC to check something out. Oops, I made a typo!
1> exec sp_msforeachdb N'
2~ use [?]
3~ select N'?', count(*) from sys.sysrscols;
4~ '
5> go
1>
Can you spot my error? Pretty obvious when you see it, right? It's even…
Peter Vandivier
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2
votes
2 answers
SQL Server Management Studio DAC connection error
I'm trying to connect to SQL Server 2012 via DAC using Management Studio. I type admin: before my server name, yet I keep getting the same error:
A network-related or instance-specific error occurred while establishing a connection to SQL Server.…
user3601171
- 21
- 1
2
votes
1 answer
Clients timing out with no apparent reason
I have a SQL Server 2005 server that's been running fine most of the time.
Today the users started to get time outs when opening new connections, including myself when I tried to open another tab on SSMS.
I've looked everywhere for the problem but I…
ivanmp
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