The ramblings of a computer geek
We had an issue where a recent Windows update broke the Exchange Server, luckily booting into safe mode and removing it resolved the issue, however although the databases mounted okay, there was one that did not. We attempted the typical ESEUTIL steps because it was reporting “dirty shutdown”, and got the database back to a … Read more
We had an issue where our RODCs suddenly stopped authenticating users and also would not allow administrators to logon via RDP or locally via the console giving this message: “there are currently no logon servers available to service the logon request” Any downstream services that were trying to authenticate via LDAP or LDAPS also failed … Read more
You want to search your Microsoft Exchange message tracking logs to track an email, you can do this using a Powershell command (run from the Microsoft Exchange Powershell console), the below command will query all your Microsoft Exchange servers to find the tracking logs and then obtain all emails sent by the user “sender@domain.com” between … Read more
Emails are made up of a header and body, the body may be HTML or plain text, and any attachments are encoded within the body of the email for it to be sent. We have applied limits to our email infrastructure to reduce load, bandwidth, and disk space but also to protect recipients of our … Read more
The lowly Format command provides some simple, yet fairly effective data destruction for hard disks that you have on your machine. Although this technique may not be suitably effective for all data destruction requirements, it is fairly thorough in the destruction of data on a disk; such as one you wish to reuse for another … Read more
We have a number of 2 node DAGs which provide our Microsoft Exchange 2016 service. Being a 2 node DAG a file share witness server is in place. We had a datacentre event that took out one of the nodes and the witness server, rendering the one of the DAGs unhealthy and a second in … Read more
We run a number of Microsoft Exchange 2016 server (yes I know we need to upgrade), these consist of four, two node DAGs with a pair of shared witness servers. For the purposes of this explanation however, we have a two node Microsoft Exchange 2016 DAG, with a single DAG Witness Server (File Share). Situation … Read more
Here’s a quick one, if you need to show a logon message to all users as they logon to a Terminal Server, for example to alert them to maintenance upcoming, there are a number of ways to do this, but this approach is a simple one. You would just add the a “Logon” script by … Read more
In certain situations the Exchange DAG witness can become a problem, this can occur during an upgrade or can happen if there is a network interruption. Although the DAG will continue to operate the witness is considered failed, which can cause odd behaviour in a failover scenario, as there is no quorum available for the … Read more
A long running issue, which I covered in my previous posts: https://geekmungus.co.uk/?p=3532 and https://geekmungus.co.uk/?p=3593, this should be taken as the current status of the problem and the resolution. Issue Following the patch: KB5021131 CVE-2022-37966, which was released November 8th 2022 we’ve continued to have some issues with Kerberos authentication to servers (devices) that use (and … Read more