--- title: CMDB Dependency Mapping | Apex Configuration Group description: How the CMDB relationship table (cmdb_rel_ci) maps dependencies between configuration items, so teams see what a change or incident actually affects. --- [![APEX CONFIGURATION GROUP](https://www.apexconfiguration.com/hs-fs/hubfs/Act3%20child/images/ACG-logo.png?width=135&height=93&name=ACG-logo.png "APEX CONFIGURATION GROUP")](https://www.apexconfiguration.com/) [![APEX CONFIGURATION GROUP](https://www.apexconfiguration.com/hs-fs/hubfs/Act3%20child/images/ACG-logo.png?width=135&height=93&name=ACG-logo.png "APEX CONFIGURATION GROUP")](https://www.apexconfiguration.com/) - [Home](https://www.apexconfiguration.com) - ServiceNow - [ServiceNow CMDB](https://www.apexconfiguration.com/servicenow-cmdb) - [CMDB Health Check](https://www.apexconfiguration.com/cmdb-health-check) - [CMDB Design & Implementation](https://www.apexconfiguration.com/cmdb-design-implementation) - [Managed Service](https://www.apexconfiguration.com/managed-cmdb-services) - [Automation & Optimisation](https://www.apexconfiguration.com/cmdb-automation-tools) - Maximising ServiceNow - [CMDB Health Dashboard](https://www.apexconfiguration.com/cmdb-health-dashboard-servicenow) - [CMDB Dependency Mapping](https://www.apexconfiguration.com/cmdb-relationship-table) - [CMDB Configuration Items](https://www.apexconfiguration.com/cmdb-configuration-items) - [CMDB Workspace](https://www.apexconfiguration.com/cmdb-workspace-servicenow) - [CMDB Best Practice](https://www.apexconfiguration.com/cmdb-best-practices) - [ServiceNow Discovery](https://www.apexconfiguration.com/servicenow-discovery-setup) - [Service Mapping](https://www.apexconfiguration.com/servicenow-service-mapping) - About - [How We Help](https://www.apexconfiguration.com/about-apex) - [What is a CMDB?](https://www.apexconfiguration.com/what-is-cmdb) - [Benefits](https://www.apexconfiguration.com/benefits-of-cmdb) - Resources - [Blog](https://www.apexconfiguration.com/blog) - [Contact Us](https://www.apexconfiguration.com/contact-us) [Contact Us](https://www.apexconfiguration.com/contact-us) [Contact Us](https://www.apexconfiguration.com/contact-us) - [Home](https://www.apexconfiguration.com) - ServiceNow - [ServiceNow CMDB](https://www.apexconfiguration.com/servicenow-cmdb) - [CMDB Health Check](https://www.apexconfiguration.com/cmdb-health-check) - [CMDB Design & Implementation](https://www.apexconfiguration.com/cmdb-design-implementation) - [Managed Service](https://www.apexconfiguration.com/managed-cmdb-services) - [Automation & Optimisation](https://www.apexconfiguration.com/cmdb-automation-tools) - Maximising ServiceNow - [CMDB Health Dashboard](https://www.apexconfiguration.com/cmdb-health-dashboard-servicenow) - [CMDB Dependency Mapping](https://www.apexconfiguration.com/cmdb-relationship-table) - [CMDB Configuration Items](https://www.apexconfiguration.com/cmdb-configuration-items) - [CMDB Workspace](https://www.apexconfiguration.com/cmdb-workspace-servicenow) - [CMDB Best Practice](https://www.apexconfiguration.com/cmdb-best-practices) - [ServiceNow Discovery](https://www.apexconfiguration.com/servicenow-discovery-setup) - [Service Mapping](https://www.apexconfiguration.com/servicenow-service-mapping) - About - [How We Help](https://www.apexconfiguration.com/about-apex) - [What is a CMDB?](https://www.apexconfiguration.com/what-is-cmdb) - [Benefits](https://www.apexconfiguration.com/benefits-of-cmdb) - Resources - [Blog](https://www.apexconfiguration.com/blog) - [Contact Us](https://www.apexconfiguration.com/contact-us) [Contact Us](https://www.apexconfiguration.com/contact-us) [tel:+442080588135](tel:+442080588135)[mailto:contact@apexconfiguration.com](mailto:contact@apexconfiguration.com) # CMDB Dependency Mapping [Book A Meeting](https://cta-eu1.hubspot.com/web-interactives/public/v1/track/click?encryptedPayload=AVxigLIuzpnrFoVNubzPnbN68LbMr217PduXcwzT3yYURg9jxT4KVBaAD0%2BQfgdjtScqT8l%2B3Xrv5jlyHQ1IMBOQgBzAX%2FJ9ZLgTWSGSr1wmqsIuMv0R8d9M8CrkkrQFGaz%2FVm3c2LwXa2rUNCA9fBMTEC6F5rSco%2F9Cj1nm%2B77FnrFJTMdiMHe6faMhQSI%2B7ojQIugSM7o%3D&portalId=147949153) [CMDB Diagnostic Call](https://cta-eu1.hubspot.com/web-interactives/public/v1/track/click?encryptedPayload=AVxigLJQMHTWIsSY3dVecreEi4sigj5TC14IQ5ZjyKttb7Uz4vQKiqQXMNRMWXtcU431oJ0w4UzDle4tKVweQWmQGzK6yeAzoNHC3p1BUjxtm01y4gSRTukdconxqk46Xjdx1inxqIwdukICQ780WhEeWBzBGPaDVc%2BHU5D%2Ftd%2B%2BHyQjSp4G6UM4R9bmlYOaai%2FdFZtc0EFI3UXKiFo%3D&portalId=147949153) ## When something fails, you need to understand the impact In complex environments, systems rarely operate in isolation. A single unplanned outage on a shared database can affect services nobody thought to check.  Applications depend on infrastructure.  Services can be comprised of multiple inter-related components.  Failures can cascade across systems with no obvious connection on paper. Without clear visibility, incidents take longer to diagnose and resolve, because the first hour goes on working out what's actually affected rather than fixing it. ### How the relationship table actually works Every row in cmdb\_rel\_ci links two configuration items through a relationship type: parent, child, and the type itself, such as 'Runs on::Runs', 'Depends on::Used by' or 'Connects to::Connects to'. The direction of that type is what makes impact analysis work: a server a database 'Runs on' is not the same relationship as a server that simply 'Connects to' it, and treating the two the same way is what makes a service map misleading. Most of the accuracy problems we see come from three sources: relationships imported by a discovery tool using its own default type regardless of what actually happened, relationships added manually when the CMDB was first built and never reviewed since, and relationships that were correct when they were created and have simply gone stale as the estate changed underneath them. Each needs a different fix, which is why a single deduplication run rarely holds. We map your existing relationship data against the specific critical success factors that predict whether it will still be accurate in six months, not just whether it exists today. That's the same lens we use in a data quality assessment: which relationships are trustworthy, which were guessed, and what's driving the difference. ![Dependency Mapping](https://www.apexconfiguration.com/hs-fs/hubfs/Dependency%20Mapping.webp?width=1125&height=844&name=Dependency%20Mapping.webp) ![Engineer holding a tablet in a data centre, with a colleague seated behind her](https://www.apexconfiguration.com/hs-fs/hubfs/Act3%20child/images/11.webp?width=1200&height=900&name=11.webp) ## Understand how your systems connect The CMDB relationship table (cmdb\_rel\_ci) is where ServiceNow stores how [configuration items](https://www.apexconfiguration.com/cmdb-configuration-items) connect to each other: which application runs on which server, which service depends on which database, which change affects which downstream system. Dependency mapping is what that table produces once the relationships in it are complete and correctly typed. It provides a clear view of: How services are delivered How services are delivered Which systems support each application Which systems support each application How failures impact other components, services, and customers How failures impact other components, services, and customers ## Why relationships matter A configuration item on its own tells you what exists. A relationship tells you what depends on it. Most CMDB projects get the first part right and skip the second, which is why the data can look complete and still fail to answer the question an incident commander actually asks. Accurate relationship information allows teams to: #### Identify root causes faster Trace an incident back through the relationship chain instead of checking each system in turn. #### Understand service impact See which business services sit downstream of a configuration item before you touch it. #### Reduce downtime Route the right team to the right system first, instead of triaging by guesswork. #### Improve incident response Give responders a map of what's connected, not just a list of what exists. #### Execute effective changes with minimal risk Check what a change actually affects before it goes to the change advisory board, not after. Without this, teams rely on manual investigation and guesswork. ## What we deliver We work directly in the relationship table rather than around it: - Accurate [CI relationship modelling](https://www.apexconfiguration.com/cmdb-configuration-items), using the correct relationship type for each connection rather than a generic catch-all link - Service dependency mapping, including [ServiceNow Service Mapping](https://www.apexconfiguration.com/servicenow-service-mapping), so a business service traces down to the infrastructure that actually supports it - Impact analysis views that show what sits downstream of a configuration item before a change is approved - Automated inter-dependency [discovery](https://www.apexconfiguration.com/servicenow-discovery-setup), so new relationships are captured as the estate changes instead of logged after the fact - The capability to build service maps that hold up under a change advisory board review, not just a diagram for a workshop ![Analyst at a desk with monitors, with a colleague working behind her](https://www.apexconfiguration.com/hs-fs/hubfs/Act3%20child/images/5.webp?width=1200&height=900&name=5.webp) ## The outcome Faster troubleshooting Clear service visibility Better Understanding of Infrastructure Dependencies ### Where this usually starts Most engagements start with the services that carry the most risk, not the whole relationship table. We map the dependencies behind a handful of critical services first, close the specific relationship types shown to be unreliable, and then extend the same fix to the rest of the estate. That order gets a service map you can trust into a change advisory board pack within weeks, rather than waiting for a full CMDB clean-up to finish first. Not sure how much of your dependency map is trustworthy? Our discovery and integration coverage review shows what's missing from your relationship data, where the gaps are, and what they cost when an incident hits.  ## Trusted by Organisations Worldwide ![Nova Action logo](https://www.apexconfiguration.com/hs-fs/hubfs/14%20(1).webp?width=144&height=90&name=14%20(1).webp) ![RTL Kockica logo](https://www.apexconfiguration.com/hs-fs/hubfs/26%20(1).webp?width=144&height=90&name=26%20(1).webp) ![RTL Living logo](https://www.apexconfiguration.com/hs-fs/hubfs/27%20(1).webp?width=144&height=90&name=27%20(1).webp) ![RTL Croatia World logo](https://www.apexconfiguration.com/hs-fs/hubfs/25%20(1).webp?width=144&height=90&name=25%20(1).webp) ![Markíza Krimi logo](https://www.apexconfiguration.com/hs-fs/hubfs/12%20(1).webp?width=144&height=90&name=12%20(1).webp) ![Nova Fun logo](https://www.apexconfiguration.com/hs-fs/hubfs/16%20(1).webp?width=144&height=90&name=16%20(1).webp) ![TV Markíza logo](https://www.apexconfiguration.com/hs-fs/hubfs/13%20(1).webp?width=144&height=90&name=13%20(1).webp) ![Nova Cinema logo](https://www.apexconfiguration.com/hs-fs/hubfs/15%20(1).webp?width=144&height=90&name=15%20(1).webp) ![TV Nova logo](https://www.apexconfiguration.com/hs-fs/hubfs/17%20(1).webp?width=144&height=90&name=17%20(1).webp) ![Nova Krimi logo](https://www.apexconfiguration.com/hs-fs/hubfs/18%20(1).webp?width=144&height=90&name=18%20(1).webp) ![Pro Cinema logo](https://www.apexconfiguration.com/hs-fs/hubfs/20%20(1).webp?width=144&height=90&name=20%20(1).webp) ![Nova Lady logo](https://www.apexconfiguration.com/hs-fs/hubfs/19%20(1).webp?width=144&height=90&name=19%20(1).webp) ![Pro TV International logo](https://www.apexconfiguration.com/hs-fs/hubfs/21%20(1).webp?width=144&height=90&name=21%20(1).webp) ![RTL Adria logo](https://www.apexconfiguration.com/hs-fs/hubfs/23%20(1).webp?width=144&height=90&name=23%20(1).webp) ![Ring logo](https://www.apexconfiguration.com/hs-fs/hubfs/22%20(1).webp?width=144&height=90&name=22%20(1).webp) ![Multiskill logo](https://www.apexconfiguration.com/hs-fs/hubfs/1%20(1).webp?width=144&height=90&name=1%20(1).webp) ![Acasă Gold logo](https://www.apexconfiguration.com/hs-fs/hubfs/2%20(1).webp?width=144&height=90&name=2%20(1).webp) ![bTV Action logo](https://www.apexconfiguration.com/hs-fs/hubfs/4%20(1).webp?width=144&height=90&name=4%20(1).webp) ![RTL Crime logo](https://www.apexconfiguration.com/hs-fs/hubfs/24%20(1).webp?width=144&height=90&name=24%20(1).webp) ![Acasă logo](https://www.apexconfiguration.com/hs-fs/hubfs/3%20(1).webp?width=144&height=90&name=3%20(1).webp) ![bTV Comedy logo](https://www.apexconfiguration.com/hs-fs/hubfs/7%20(2).webp?width=144&height=90&name=7%20(2).webp) ![Dajto logo](https://www.apexconfiguration.com/hs-fs/hubfs/9%20(2).webp?width=144&height=90&name=9%20(2).webp) ![bTV Cinema logo](https://www.apexconfiguration.com/hs-fs/hubfs/6%20(2).webp?width=144&height=90&name=6%20(2).webp) ![Doma logo](https://www.apexconfiguration.com/hs-fs/hubfs/10%20(3).webp?width=144&height=90&name=10%20(3).webp) ![bTV Story logo](https://www.apexconfiguration.com/hs-fs/hubfs/8%20(3).webp?width=144&height=90&name=8%20(3).webp) ![RTL Passion logo](https://www.apexconfiguration.com/hs-fs/hubfs/28%20(1).webp?width=144&height=90&name=28%20(1).webp) ![bTV logo](https://www.apexconfiguration.com/hs-fs/hubfs/5%20(2).webp?width=144&height=90&name=5%20(2).webp) ![RTL 2 logo](https://www.apexconfiguration.com/hs-fs/hubfs/29%20(1).webp?width=144&height=90&name=29%20(1).webp) ![TN CZ logo](https://www.apexconfiguration.com/hs-fs/hubfs/30%20(1).webp?width=144&height=90&name=30%20(1).webp) ## Structured Delivery Process Structured approach. Clear outcomes. No overengineering Step 1 Step 2 Step 3 Step 4 ### 1. Assess & Diagnose Comprehensive assessment of your current CMDB state, data quality, and automation maturity.  ### 2. Design for Clarity Architect a CSDM-aligned data model and automation framework tailored to your environment.  ### 3. Implement & Automate Build automated discovery, data validation, and self-healing processes for sustained accuracy.  ### 4. Govern & Optimise Establish governance frameworks, KPIs, and continuous monitoring to maintain CMDB health.  Trusted By Fortune 500 Enterprises | ServiceNow Certified Experts ## Ready To Gain Control & Clarity? Partner with specialists who deliver accurate, automated, and resilient CMDBs for enterprise organisations. 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