Explaining SQL Server in plain english
TLDR: Nope.
Keep on doing your full backups.
Make sure that any databases you Log Ship are NOT also doing log backups in your SQL Maintenance Plans, Ola Jobs, etc.
The Backup Chain will not be broken by running a Full backup, and you do not need to use Copy-Only
Proof:
Thanks for reading!
SQL Server maintains a variety of stats about all sort of performance items.
I was trying to troubleshoot some TerriBad * tempdb write performance…almost 3000ms per write, on a server that we recently migrated to.
Our data center vendor of course said the storage was perfect and that we should try troubleshooting SQL Server. (Duh?)
These stats are stored in the sys.dm_io_virtual_file_stats DMF, and I found this gem under the ‘sample_ms’ column description in the result set:
“The data type is int for SQL Server 2008 through SQL Server 2014 (12.x). In these versions, the value will reset to 0 after approximately 25 days of continuous database engine uptime.”
Now, this is a SQL 2017 box, but this tells me that these stats are going to reset at some point.
When I re-ran my IO stalls query…the writes for all 8 tempdb data files are at 7ms. The sample_ms is currently 3,097,351,985 which is about 36 days if I’ve done my math right. Server uptime is approaching 90 days.
The takeaway for you, dear reader, is to know where to find the stats but also to know what timeframe they represent.
* Thanks to Brent Ozar (b|t) for this highly amusing term 🙂
Thanks for reading!
Welcome back to the series “Server Review Essentials for Accidental and Junior DBAs.” So far in this series we’ve taken a look at how to set up your work environment, best practices for onboarding new servers and clients, and prepping your servers for daily reviews.
After all of our work and prep during the last several posts in this series, it’s finally time to get down to the “real” work of a DBA.
Wait, that’s not quite right. While it may seem as if everything covered so far in this series has been pretty basic and production servers have barely been touched, don’t get the idea that the work done so far isn’t of high value. Think about some of the things you’ve already learned about your servers during this preparation process:
Why is all of the above so vital? If I’ve learned one thing in my two years of database administration it’s that there seems to be a large number of folks who really have no clear understanding of what’s going on in their server environments. Their approach to preserving their data is more seat of the pants and reactionary than proactive monitoring.
As outside consultants, these are the types of folks who typically end up calling us to say, “my server is on fire!” Many of the issues we see on an “emergency” basis could have been prevented with regular reviews.
At Dallas DBAs, we much prefer a proactive approach to database maintenance and performance. When we take on a new group of servers, the first thing we do is run a health check on the boxes and search for any issues that may need immediate remediation or any server settings that can be adjusted for immediate benefit.
While these topics are not covered in this series, we’re often looking for common issues related to things such as Cost Threshold for Parallelism, Instant File Initialization, MAXDOP, max server memory, the current state of backups, TempDB configuration, and more.
This gives us a launchpad to implement all of the prep work mentioned in this series so far, and better guide the people who are depending upon the data to run their business or otherwise get work done.
By taking a proactive approach, we often know about problems days or hours before our clients do. We can see if backups have failed, ensure index maintenance is occurring regularly, and keep an eye on job failures and errors.
We often prefer to do a quick 15 minute or less check of all servers daily, running a handful of scripts that I’ll begin sharing in the next few posts. These scripts quickly show us the state of the backups, reveal any job failures or errors we need to investigate, and find alerts we may need to be aware of.
This proactive approach also helps us get to know what is expected from the servers. As we report job failures and errors, we may learn that certain issues are common knowledge and are not necessarily causing the end-users any pain.
We learn how our data users feel about deadlocks. They may not care about them if they don’t “feel” them. A job that runs every 10 minutes and is the victim of a deadlock once or twice a day likely isn’t going to be an issue. Sometimes job failures are simply random “network blips” that happen periodically, so all you can do is name a note, shrug your shoulders, and move on.
That’s all for now. Next time we’ll take a deeper dive into looking at investigating your server’s backup history.
If you’d like to know more about SQL Server Maintenance, check out Kevin’s Getting Started with SQL Server Maintenance course at Pluralsight.
Follow me on Twitter at @SQLandMTB, and if you’re into mountain bikes come over and check out my site NTX Trails.
Welcome back to our series, Server Review Essentials for Accidental and Junior DBAs, where we’ve been taking an in-depth look at how to get ready to perform regular SQL server reviews for your company or clients. So far, we’ve covered how to get your working environment set up (Part 1 | Part 2) setting up biographical information about your environments, collecting server information, building a maintenance job list, and backup frequency list, as well as providing sample biographies and server reports.
Now it’s time to move forward and put all your preparation to use and perform regular server checks…almost. We’ve got one more round of prep work to do before your environment is completely ready to go.
Before you go any deeper into this process, now is the time to ensure all of the servers you’ve been entrusted with are meeting the stated Recovery Point Objectives. My advice at this point is to not worry over the Recovery Time Objective until you’ve ensured you’re meeting RPO. Your company or clients won’t care how fast their data can be recovered if they can’t recover the data they actually need.
Use the backup frequency list you created in an earlier step and take the time to look through each server to see if the backup schedule meets the stated RPO in terms of FULL and LOG backup frequency (and DIFFs if relevant). We’re not confirming the existence of the backups yet, we’ll do that in a later step. For now, just make sure the backup jobs are scheduled properly to meet your RPO requirements.
If you find that your backup jobs are not scheduled properly, get with your senior DBA or the relevant person in authority and correct the backup job schedules accordingly.
Though not necessary, I’d suggest creating your own DBA Tools database on each of the servers for which you are responsible. Most companies and clients won’t have any problem adding such a database since it is lightweight, provides tools beneficial to your server health, and creates a sandbox in which those tools can reside separately from the data.
This is a common method for us here at Dallas DBAs. Whenever we’re given the responsibility for administrating a new server or environment, one of the very first things we do is evaluate the current state of the server, implement some best practices, and create a new database like this to install our preferred scripts.
We’re not going to cover the steps to creating a new database for your tools. If you don’t know how to do that, check out the Microsoft Docs to learn how to make a new database. Having said that, we feel it’s always best to put the database in SIMPLE recovery model and make sure the database owner is “sa”. Otherwise, you can pretty much use the defaults in creating your new DBA Tools database.
What scripts do we install and use regularly? In the following posts in this series we’ll showcase some of the scripts we use, but below you’ll find a list of scripts and stored procedures we like to implement on the servers we touch.
Keep in mind the purpose of this post is not to explain how to install or use any of the scripts and tools listed below, only to show you some of the tools we like to use.
Now your servers are primed for regular reviews, which means you will often know about potential issues long before they become catastrophic failures. Having done all of this work doesn’t guarantee your servers will be problem-free, but it does mean your servers will be less likely to suffer common issues and you’ll be better equipped to handle issues as they arise.
If you’d like to know more about SQL Server Maintenance, check out Kevin’s Getting Started with SQL Server Maintenance course at Pluralsight.
Follow me on Twitter at @SQLandMTB, and if you’re into mountain bikes come over and check out my site NTX Trails.
Let’s take a look at the final few steps of your initial server intake process and get your workflow up and running as you push toward performing regular server reviews. These last few steps are relatively easy and quick to set up.
(Also see Part 1, Part 2, and Part 3 of this series)
Now that you’ve set up your Maintenance Job list, you should be able to see how backups are scheduled for your servers. This is the point where you begin pushing from simply gathering info on your servers towards ensuring your servers are set up correctly.
Depending on your situation and environment, you may not need to create an actual list in a document or spreadsheet. Sometimes simply having a familiarity with what databases are backed up and their frequency is enough, but it may be best to create an actual list in the beginning.
You’ll need to be able to determine what types of backups are happening—FULLs, DIFFs, LOGs—and when those backups occur. Once you’ve collated this information then you’re ready to see if the current backup scheme meets the expected Recovery Point Objective and Recovery Time Objective. If not, then getting your backups whipped into shape should be the first task you assign yourself for your new servers.
I’m personally at the point where I have enough servers spread across different environments that I need to create a new writeup of backup schedules for those environments. There are currently too many environments to keep straight in my head, which means it’s far too easy to miss whether or not a particular server group’s backups are on schedule and up-to-date.
How so? Some of the server groups I check are scheduled to create Full backups daily, while others are only creating these backups weekly. I have some server groups in which there’s a mix of scheduling, and others that have either native SQL Server backups, virtual device “snapshot” backups, or sometimes both. One client in particular has two server groups that I check regularly, one of which is using native SQL Server backups while the second group is primarily using virtual device backups.
So, if you decide to write up an actual list, what do you include? Here’s a not-so-comprehensive list of items you may want to include in your document:
The above is simply a sampler of items you may choose to include. Again, depending on your environment and SLAs, your list might look somewhat different.
Now that you’ve gotten all of your server’s baselines gathered you’re ready to start implementing regular checks. How often you perform these server reviews will depend on your employer’s dictates or current SLAs. For me, I currently have several server groups I check daily, one server group that is checked twice per week, and one server group that is only checked once per week.
What’s included in my regular reports? In the coming weeks I’ll be stepping through how I get my reviews done, but for now I’m including a sample report below so you can get a sense of the sorts of items you’ll be looking over as you check your servers.
ABC Server Review 03-22-2021
Servers:
Unable to connect to ABC-SQL-03. Upon ping "Ping request could not find host ABC-SQL-03.".
Recommend applying CU22 for SQL Server 2017 and Security update for SQL Server 2017 CU22: January 12, 2021 [CVE-2021-1636] to ABC-SQL-01.
Third Party Monitor:
If there are any third party monitoring products in use—such as Solarwinds DPA or Redgate Monitor—any current alerts get notated here.
Replication:
ABC2020_Pub5 is reporting Critical performance.
All other publications are reporting Excellent performance.
Jobs:
The job 'Write Stuff to the Table' failed at step 'Load Stuff' on ABC-SQL-01 on 03-21-21 at 4:00 AM. This job is scheduled to run hourly and failed previously on 03-17-21. The job has executed successfully since 03-21-21 at 5:00 AM.
The job was the deadlock victim.
Backups:
All backups are up to date.
Errorlogs:
Login failure for user 'ABC\lcage' on ABC-SQL-02 on 03-21-21 at 7:36 AM. Reason: Could not find a login matching the name provided. [CLIENT: 100.10.10.1]
66 deadlocks on ABC-SQL-02 on 03-21-21 through 03-22-21.
Alerts:
No alerts to report.
AG Health
All Availability Groups reporting Healthy.
Other:
Your own reports may look significantly different than what you see above. Obviously, if your servers are not using features such as replication or Availability Groups then there’s no need to include them in your report. Depending on your employer’s or client’s expectations—and your SLAs—your report may be more or less detailed. You may even have some sort of ticketing system in place.
In my case, I send my reports to my senior, Kevin, as an attachment to an email for his review. I’ll note any items I believe are critical and need immediate attention in the body of the email and highlight them in red text. There are certain issues which are appropriate for someone at my level that I will rectify on my own, otherwise Kevin and I will address issues together, or he will contact the necessary personnel who oversee particular aspects of the servers as needed. This is the workflow that works for us, but your practices and procedures may look different.
At this point, you may need to go even deeper and to build a full server inventory which is more comprehensive than what I’ve laid out in the last few posts.
This may also be the point where you need to do a full Health Check on your servers and look for any best practices that need to be implemented and note any problems you find that need to be addressed. Create a list of these items and your suggested recommendations for remediation, as well as a potential schedule of when and how it might be best to address these issues.
Stay tuned! In the next group of posts we’ll start an overview of implementing server monitoring and active reviews.
If you’d like to know more about SQL Server Maintenance, check out Kevin’s Getting Started with SQL Server Maintenance course at Pluralsight.
Follow me on Twitter at @SQLandMTB, and if you’re into mountain bikes come over and check out my site NTX Trails.
The next post of this series is finally ready to fly. I apologize for the delay between posts, but between the rolling blackouts in Texas during the 2021 Snowpaclypse and a personal health issue, getting this written was a struggle. Let’s get back to it and take a look at the final steps in the client onboarding process.
(Also see Part 1 and Part 2 of this series)
Now that we’ve taken a look at getting the biographical data for your servers gathered, the next step is to take an inventory of the maintenance jobs that are already set up and running on your servers. We mainly want to see if proper backups are taking place, and whether or not common tasks such as integrity checks and index maintenance jobs exist. At this point we’re not concerned whether or not things are set up correctly, we only want to assess what is or is not happening so we can put together an effective plan for future data protection and preservation.
Gathering this information is easy, while deciding what to do with it will take some thought.
This can be somewhat tedious if you’re managing several instances of SQL Server, but here’s a quick way to find and chart the information you’re looking for.
In SSMS, open up your target instance in Object Explorer, then drill down to SQL Server Agent >> Jobs >> Job Activity Monitor.
This tutorial assumes the SQL Server Agent is running on your instance.
Double-click the Job Activity Monitor to open up a new window that should look something like this:
Now you can copy/paste this information into an Excel spreadsheet if you’d like to have a local copy of this information to work with. You’ll be limited to keyboard shortcuts to select all and copy—there’s no right-click “Copy with headers” available in this window.
You can see on my machine I have Ola Hallengren’s SQL Server Maintenance Solution installed to take care of all the basic maintenance tasks, as well as some addition useful maintenance jobs. In your situation, you may find similar results, a collection of Maintenance Plan jobs, or a different set of jobs altogether. Hopefully, you find something that’s already been set up to take care of backups, integrity checks, and index maintenance.
From here, you can see what jobs are active, when those jobs last executed successfully, and get a sense of the job’s schedule. Remember, at this stage of the onboarding process we’re more concerned with what jobs are set up rather than if they are set up properly.
Gathering this information will allow you to make informed recommendations and decisions going forward from this point. You’ll begin to be able to determine if the current job maintenance schedule meets your company’s Recovery Point Objectives (RPO) and Recovery Time Objectives (RTO). If so, great, you’re in good shape! If not, then you’ve got some work ahead of you to get your maintenance jobs in order.
Once you have this information gathered and collated, you’ll be ready to tackle the next step in the onboarding process, which is building a backup frequency list. We’ll take a look at that issue in the next post.
If you’d like to know more about SQL Server Maintenance, check out Kevin’s Getting Started with SQL Server Maintenance course at Pluralsight.
Follow me on Twitter at @SQLandMTB, and if you’re into mountain bikes come over and check out my site NTX Trails.
