Hi @Abid, Kamel ,
Thank you for posting this question on Microsoft Q&A.
I see that you are exploring services available to visualize dependencies through service map in Azure for Azure VMs. There are 2 different options available for it.
1. Using Service Map Solution in Azure Log Analytics, as mentioned in the question.
To use Service maps, you would add it to the Log Analytics workspace as solution. It is available at no cost, but it collects data which is stored in the Log Analytics Workspace which would invoke usage charges. The pricing details for Log Analytics workspace are available here - Azure Monitor pricing. Since the usage charge would depend on the type of workload that you have on your VMs, using it for your test environment for a while should give you an idea of the amount of data being collected.
2. VM Insights - This is also based on the data collected in Log Analytics workspace, therefore the usage charge would depend on the amount of data being ingested and stored.
For difference between these 2 solutions, please see How is VM insights Map feature different from Service Map?
Please let me know if you have any questions.
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