The 300-410 ENARSI (Implementing Cisco Enterprise Advanced Routing and Services) certification exam plays a pivotal role within the Cisco Certified Network Professional (CCNP) Enterprise track. This exam is tailored for networking professionals who want to deepen their understanding of advanced routing and services in enterprise environments. It is considered one of the more technical specialty exams under the CCNP umbrella and is often chosen by those aspiring to become senior network engineers or specialists in routing protocols and network troubleshooting.
ENARSI takes a deep dive into Layer 3 routing protocols, VPN solutions, infrastructure services, and network troubleshooting. Candidates preparing for this exam are expected to move beyond theory and demonstrate a hands-on understanding of how routing protocols operate and interact in live networks. It's not just about knowing what OSPF or BGP is, but about being able to configure, validate, and troubleshoot these protocols in real-time scenarios that simulate actual enterprise demands.
The 300-410 exam is also a marker of professional maturity in networking. While the CCNA establishes foundational skills, ENARSI builds the bridge to roles that require real-time problem resolution and advanced design implementation. Engineers who pass this exam are trusted to make configuration changes on critical infrastructure, mitigate routing loops, identify asymmetric routing behavior, and configure secure VPN tunnels—tasks that, if done incorrectly, can lead to major network outages.
What makes this exam especially valuable is its heavy focus on operational efficiency. You’re tested on how well you understand concepts such as route redistribution between different protocols, policy-based routing (PBR), and the nuances of controlling routing updates using prefix-lists, route-maps, and distribute-lists. Each of these configurations is commonly deployed to maintain the consistency, security, and performance of routing domains across diverse business networks.
Another important aspect of the ENARSI certification is its attention to VPN technologies. The exam covers key solutions like DMVPN, IPsec, and FlexVPN, which are increasingly important as organizations adopt hybrid cloud models and need secure site-to-site communication. Being able to troubleshoot tunnel establishment failures, misconfigured ISAKMP policies, or encryption mismatches is essential for engineers responsible for remote connectivity in secure enterprise environments.
Beyond routing and VPNs, ENARSI extends into infrastructure services such as network time protocol (NTP), Simple Network Management Protocol (SNMP), and syslog configuration. These services, while sometimes overlooked in entry-level certifications, are vital in real-world enterprise deployments. For example, ensuring all routers and switches sync to a reliable NTP source prevents troubleshooting anomalies caused by time discrepancies in logs. Likewise, SNMP and syslog are crucial for centralized monitoring, helping engineers respond proactively to failures or abnormal behavior.
A key strength of this certification lies in its emphasis on high availability (HA) and redundancy. Technologies like Hot Standby Router Protocol (HSRP), Gateway Load Balancing Protocol (GLBP), and Virtual Router Redundancy Protocol (VRRP) ensure that network access remains uninterrupted in the event of hardware or link failures. The ENARSI exam expects candidates to not only configure these protocols but also interpret their roles in failover and performance optimization scenarios. Understanding how to fine-tune hello/dead intervals, track interfaces, and implement object tracking directly translates into more stable and resilient network designs.
The troubleshooting capabilities evaluated in this certification are perhaps its most demanding element. Real-world enterprise networks are rarely perfect, and unexpected issues are commonplace. Engineers must be comfortable using show, debug, and logging tools to assess conditions like neighbor relationship failures in routing protocols, MTU mismatches, or misrouted traffic. The ability to isolate problems efficiently without causing further disruptions is a critical skill in today’s fast-paced IT environments.
Preparation for the 300-410 exam involves a combination of theory, configuration practice, and scenario-based analysis. Most successful candidates build virtual labs using tools like Cisco Packet Tracer or GNS3, simulating complex routing topologies that combine EIGRP, OSPF, and BGP. By troubleshooting these topologies under failure scenarios—such as route filtering errors or IPsec tunnel drops—engineers learn to adapt quickly and diagnose under pressure. This type of hands-on, iterative practice cements long-term understanding far better than studying syntax alone.
The value of ENARSI also lies in its recognition across the industry. Whether you are aiming to join a managed service provider, a large enterprise IT department, or even pursue freelance consulting, this certification signals a high level of technical proficiency. Employers view ENARSI-certified professionals as network engineers capable of overseeing critical deployments and leading troubleshooting efforts when things go wrong. This trust can open doors to more senior roles, lead positions, or specialist jobs focused on routing and security.
In today’s enterprise networking landscape, where hybrid infrastructure and software-defined technologies are becoming the norm, the ENARSI certification also provides foundational support for transitioning into areas like SD-WAN, network automation, and security integration. Although the exam focuses primarily on traditional routing and services, the skills gained—such as understanding policy control, managing redundancy, and building secure communication paths—translate well into emerging domains. This makes ENARSI not only valuable today but future-proof for what lies ahead.
Ultimately, preparing for and passing the 300-410 ENARSI exam represents a major investment in your networking career. It reinforces the habits of methodical troubleshooting, logical thinking, and precision configuration that are essential to being an effective network engineer. It challenges you to go deeper than surface-level understanding and to develop operational instincts that will serve you across a range of enterprise architectures.
The certification does more than validate your skills; it instills the confidence to tackle complex networks, lead migration projects, and design solutions that scale reliably. Whether your goal is professional advancement, deeper specialization, or simply mastering the craft of enterprise networking, ENARSI offers a clear and respected path to achieving it.
The 300-410 exam measures the candidate’s ability to configure, operate, and troubleshoot complex routing technologies and services. It focuses on advanced Layer 3 technologies such as EIGRP, OSPF, and BGP, but it goes beyond basic configuration. Candidates are tested on their ability to implement security features like route redistribution filtering, authentication, and VPN services such as DMVPN and IPsec. The inclusion of troubleshooting also requires professionals to be comfortable with interpreting routing tables, analyzing packet flows, and using Cisco IOS tools to diagnose network issues.
The exam is a 90-minute assessment delivered in a multiple-choice and simulation format. Candidates are required to demonstrate both theoretical knowledge and practical skills. Unlike entry-level exams, ENARSI emphasizes real-world scenarios where candidates must make configuration choices or interpret output from devices. The exam is part of the specialization track and assumes familiarity with the foundational topics covered in the 350-401 ENCOR core exam.
Successfully passing the 300-410 ENARSI exam not only moves you closer to achieving full CCNP Enterprise certification but also affirms your capability to design and maintain robust, scalable, and secure network infrastructures. The certification is especially beneficial for roles that demand strong routing knowledge, such as network engineer, enterprise infrastructure specialist, or Tier 3 network support. It reflects a high level of technical depth and is often seen as a differentiator in competitive IT environments.
A major portion of the 300-410 ENARSI exam focuses on routing protocols at an advanced level. While many candidates come into this exam with basic EIGRP, OSPF, and BGP knowledge, the exam requires a deeper technical understanding that includes route redistribution, filtering, summarization, and path control techniques. Candidates are expected to manage scenarios where multiple routing protocols coexist, and fine-tuned redistribution becomes necessary to maintain network stability and routing efficiency.
In EIGRP, the exam explores manual summarization, stub routing, authentication, and troubleshooting route flapping or convergence delays. OSPF knowledge must go beyond single-area configuration; multi-area OSPF, LSA types, and area types such as NSSA and totally stubby are critical. Understanding how OSPF reacts to topology changes or redistribution from external protocols is often tested in simulations.
BGP, a crucial protocol in enterprise-to-service-provider scenarios, is evaluated through its configuration in both internal and external settings. Candidates must master route filtering using prefix-lists and route-maps, understand the BGP decision process, and interpret path attributes like AS_PATH, LOCAL_PREF, and MED. The exam also expects an understanding of BGP peering states, neighbor relationships, and the use of private versus public autonomous system numbers.
Beyond standard routing, the ENARSI exam evaluates Layer 3 technologies that enhance redundancy, scalability, and security. High Availability protocols such as HSRP, VRRP, and GLBP are tested not only for their basic setup but also for failover testing and preemption behavior. You must understand how these protocols work in both IPv4 and IPv6 environments.
Additionally, the exam delves into multicast routing, including PIM sparse mode, RP placement, and IGMP operations. This is particularly relevant for enterprise networks that use video or voice technologies. Though not every organization relies on multicast, Cisco expects CCNP-level candidates to be fluent in how these technologies function and interoperate with unicast routing.
The inclusion of VPN services in the 300-410 exam is a strong indicator of its relevance to real-world enterprise networking. Dynamic Multipoint VPN (DMVPN) is a major topic, and candidates are tested on hub-and-spoke topologies, NHRP, IPsec integration, and multipoint GRE tunnels. You must understand how phase 1 and phase 2 of DMVPN function and how to troubleshoot common issues like tunnel flapping or encryption mismatches.
Site-to-site VPNs using IPsec are also included. The focus is not just on tunnel creation but on the flexibility and security of these connections. Troubleshooting encrypted tunnels is often emphasized, where candidates must use show and debug commands to identify phase 1 or phase 2 negotiation failures.
The 300-410 ENARSI exam heavily emphasizes troubleshooting as a core competency. Unlike entry-level certifications that test your ability to configure or identify protocols, this exam challenges your ability to detect, isolate, and fix issues across Layer 3 and VPN services in complex topologies. For this reason, successful candidates must go beyond textbook configurations and deeply understand command-line diagnostics, logical analysis, and real-world network behavior.
At this level, you’re often expected to troubleshoot route redistribution, adjacency issues, control plane disruptions, and misconfigured VPNs—all while maintaining minimal downtime. Troubleshooting scenarios in the exam often simulate partial connectivity, asymmetric routing, or unexpected failover behavior. These aren’t just configuration issues; they test your ability to understand the symptoms and isolate the fault domain quickly and accurately.
EIGRP-related problems in ENARSI often revolve around neighbor adjacency failures, route filtering, and summarization errors. For example, if an EIGRP neighbor fails to form an adjacency, you’re expected to check for mismatched autonomous system numbers, incompatible K-values, and incorrect passive interface settings. The command show ip eigrp neighbors is essential for diagnosing peer states.
Another common scenario involves summarization issues. If a manual summary is configured on an interface but an important subnet is excluded, traffic can be black-holed. Candidates must be able to identify this through the use of show ip route, show ip protocols, and trace-based verification.
Route filtering using distribute-lists or route-maps also presents a challenge. If filters are applied incorrectly, certain routes may not be advertised or accepted, leading to broken connectivity. Debug commands such as debug eigrp packets can offer insights into route advertisement and neighbor exchange behavior.
OSPF troubleshooting focuses on neighbor relationships, area design problems, LSA propagation, and path selection inconsistencies. A common exam topic is diagnosing why routers within the same area are not forming adjacencies. This could be due to mismatched area IDs, MTU mismatches, or hello/dead timer discrepancies.
Understanding the OSPF database is critical. Using show ip ospf database, you can inspect the types and sources of LSAs, identify missing advertisements, or verify that stub and NSSA configurations are correct. Sometimes, virtual links or backbone area misconfigurations are at the heart of reachability problems.
One complex topic in ENARSI is route summarization and its impact on OSPF path selection. Misuse of summary-address commands can lead to suboptimal routing or even loops. Route maps used in redistribution between OSPF and other protocols must be carefully constructed and verified using show route-map, show ip ospf, and debug ip ospf events.
BGP problems are often misunderstood because of its unique behavior compared to IGPs. The ENARSI exam expects you to troubleshoot both eBGP and iBGP problems including peer establishment, path selection, and route filtering. If a BGP session doesn’t come up, it may be due to mismatched AS numbers, incorrect IP addresses, or missing update-source and ebgp-multihop configurations for iBGP peers.
One difficult aspect is troubleshooting missing prefixes. Just because a route is in the BGP table doesn’t mean it’s in the routing table. Use show ip bgp to verify prefix existence and path attributes, and show ip route to confirm whether the best path is installed. Path selection logic—based on weight, local preference, AS path length, origin type, MED, etc.—must be understood intuitively to predict and verify routing decisions.
Prefix-lists and route-maps are powerful tools but can also be sources of failure if misapplied. Troubleshooting them requires checking their sequence logic, applying show ip prefix-list, and confirming their association with BGP neighbors using show ip bgp neighbors.
The ENARSI exam includes scenarios on high availability using HSRP, VRRP, and GLBP. Troubleshooting these protocols involves detecting failover failures, misconfigured priorities, or incorrect group numbers. For HSRP, use show standby to verify active and standby roles, timers, and preemption settings. One tricky issue occurs when preemption is disabled, and a lower-priority router continues to act as active.
Tracking interfaces is another often-overlooked feature. If tracking is misconfigured, failover may not occur even when an upstream link fails. Verify using show standby brief and confirm that the tracked objects exist and decrement values are applied.
GLBP-specific issues could stem from weighting misconfigurations or AVG/AVF role disputes. VRRP, being more static, usually fails due to group mismatches or incorrect IP assignments.
VPN problems are some of the most complex in ENARSI, especially when IPsec or DMVPN is involved. A common scenario involves tunnel interfaces flapping or traffic failing to pass through. Troubleshooting begins by checking the tunnel interface status (show interface tunnel x), then reviewing the NHRP cache for DMVPN (show dmvpn, show ip nhrp), and finally validating IPsec with show crypto isakmp sa and show crypto ipsec sa.
One of the frequent challenges is split-horizon behavior in DMVPN Phase 2. Without disabling split-horizon or using NHRP redirect, spokes may fail to reach other spokes directly. Candidates must identify this based on traffic patterns and topology layout.
Encryption mismatches, pre-shared key errors, or incorrect transform sets also cause IPsec tunnels to fail. The debug command set—debug crypto isakmp, debug crypto ipsec—can pinpoint where in the negotiation the failure occurs. In some cases, NAT traversal or incorrect ACLs can block tunnel establishment entirely.
Route redistribution is a critical skill tested in complex hybrid environments where multiple routing protocols coexist. One common problem is route filtering at redistribution points, where route-maps or prefix-lists prevent certain subnets from entering another protocol’s domain. The exam often challenges candidates with asymmetric routing or missing route scenarios caused by incorrect metrics or tags.
A route redistributing from EIGRP into OSPF, for example, might be rejected if the seed metric is not defined. Similarly, route-maps used in redistribution might have incorrect match statements or deny routes unintentionally. Use show route-map, show ip protocols, and show ip route to correlate the issue with the filtering logic.
A subtle problem involves routing loops when subnets are injected back and forth between protocols. Tagging routes and filtering based on those tags is a common solution but must be implemented correctly to avoid breaking the routing domain.
Cisco IOS provides a wide set of tools to assist in troubleshooting. The show and debug commands are primary tools, but their output must be interpreted with care. For example, using show ip cef can identify CEF switching issues or FIB inconsistencies, while show ip arp can help confirm L2/L3 reachability problems.
Ping and traceroute are still foundational tools, especially when paired with extended options such as source IP or specific VRFs. Using ping vrf x or traceroute vrf y helps isolate issues in MPLS or multi-VRF environments.
Another underutilized tool is conditional debugging, where specific events are monitored only under defined conditions. This helps narrow down issues in large networks without being overwhelmed by debug output.
A critical component of success in 300-410 is not just knowing what commands to run, but knowing how to think. Effective troubleshooting requires isolating the problem domain—determining whether the issue lies in Layer 1, 2, or 3. Once routing is confirmed as the problem, determine whether it's due to reachability, path selection, or protocol-specific behavior.
A proven methodology is the "bottom-up" or "top-down" approach. In a bottom-up strategy, you confirm link and interface status before evaluating routing protocol operation. Top-down troubleshooting begins from the application layer and works down to the transport and network layers.
In large networks, documentation, baseline behavior, and configuration history play a role. If you’re preparing for ENARSI, practice troubleshooting in environments with change control, simulated outages, and redundant paths. Learn to use archive, logging, and rollback features to analyze historical configurations or restore stable states quickly.
One of the most critical aspects of the 300-410 ENARSI exam is its emphasis on advanced troubleshooting. While configuration is still part of the evaluation, Cisco expects candidates to demonstrate a deep understanding of how to isolate, diagnose, and resolve network problems quickly and effectively. This section of the exam goes beyond textbook scenarios and requires adaptive thinking.
Candidates must be proficient in using Cisco IOS commands for detailed packet flow analysis. Commands like show ip route, show ip cef, show interface, and debug tools become essential for pinpointing connectivity issues. For instance, when a route isn’t appearing in the routing table, understanding whether it’s an administrative distance issue, filtering problem, or redistribution conflict is key. Similarly, identifying asymmetric routing or recursive next-hop errors in BGP requires more than just surface-level knowledge.
Another dimension of troubleshooting in the exam is recognizing misconfigurations in Layer 3 protocols, such as routing loops caused by summarization at the wrong boundary or prefix-list errors leading to route drops. Troubleshooting these errors often involves dissecting complex topologies, so visualizing traffic flow and dependency paths is essential.
Moreover, troubleshooting scenarios in the exam may involve technologies like VRFs and GRE tunnels, where isolation makes the process more challenging. Understanding how to trace connectivity across VRF instances or through encrypted VPN tunnels reveals your readiness for real-world scenarios.
The 300-410 exam evaluates a network professional’s ability to work with infrastructure that mirrors enterprise environments. This includes the ability to implement and control routing policies, traffic engineering, and optimized path selections.
Policy-Based Routing (PBR) is a prominent feature in ENARSI. It allows for granular control over traffic flow that goes beyond destination-based routing. The candidate must understand route maps, match conditions, set actions, and apply them to interfaces or globally. This is especially important in environments where service chaining, load sharing, or policy-specific forwarding is required.
Another significant component is route filtering and redistribution. Real-world networks rarely use a single routing protocol, so understanding how to translate routing information between OSPF, EIGRP, BGP, and RIP using route maps, prefix lists, and distribute-lists is essential. The exam may challenge you with loop prevention, metric translation, and administrative distance adjustments.
Infrastructure security and integrity are also crucial. You’re expected to use tools like uRPF (Unicast Reverse Path Forwarding), routing protocol authentication (MD5 for OSPF or EIGRP), and control plane policing (CoPP) to secure your network against threats and misbehavior.
Maintaining the performance and stability of a network goes beyond initial deployment. The 300-410 exam places importance on continuous monitoring and performance tuning using a combination of SNMP, NetFlow, and IP SLA.
You must be able to configure and interpret SNMP traps and use NetFlow to analyze bandwidth utilization and traffic patterns. These tools allow enterprise network administrators to identify bottlenecks, peak usage periods, and application-level traffic concerns. IP SLA, on the other hand, helps simulate real-time traffic to measure latency, jitter, and loss—vital for voice and video applications.
Logging, syslog servers, and SNMP traps are not just about configuration—they play a major role in proactive network health monitoring. The exam assesses your ability to correlate event logs with real-time traffic anomalies or route changes. For instance, detecting OSPF neighbor flaps or BGP session resets through timestamps can indicate interface flapping, faulty links, or external provider issues.
Performance tuning using queueing strategies, such as class-based weighted fair queueing (CBWFQ) and traffic shaping/policing, might also be assessed. These ensure traffic prioritization during congestion and are critical for maintaining QoS standards.
Simulation labs make up a large portion of the exam experience. These labs are designed not just to test configuration memory but to evaluate how you apply logic under constraints. Often, the scenario will not include all the required information, and you must investigate live device output to identify and solve the problem.
For example, a lab might present a network where an OSPF route is missing in a specific location. Your task will be to determine whether the problem lies in OSPF adjacency, area configuration, route filtering, or interface-level issues. Each lab task will typically build on the previous one, making accuracy from the start crucial.
Hands-on practice in a lab environment, such as using Cisco Packet Tracer or GNS3 with real IOS images, is a vital part of preparation. This allows you to not only learn the commands but to develop muscle memory for navigating configuration modes, analyzing outputs, and implementing changes without disrupting existing services.
The 300-410 ENARSI exam includes IPv6 technologies, often embedded within broader scenarios. Candidates must not only configure routing protocols like EIGRP for IPv6 and OSPFv3 but also troubleshoot dual-stack environments.
IPv6 brings new elements such as link-local addresses, neighbor discovery, and unique addressing strategies that differ from IPv4. When troubleshooting, it’s important to remember that IPv6 routers form adjacencies using link-local addresses, which might confuse candidates expecting global unicast communication.
Routing policies must also be adapted for IPv6. Prefix-lists, access-lists, and route-maps must be written for IPv6 syntax and logic. Redistribution and filtering also apply to IPv6, and mixing protocols like EIGRPv6 with OSPFv3 requires nuanced metric handling and policy enforcement.
Dual-stack challenges include ensuring that routing is symmetrical across both IPv4 and IPv6 paths, managing DNS resolution in both spaces, and troubleshooting reachability where only one protocol may work due to firewall rules, ACLs, or NAT64-related issues.
Many candidates underestimate the difficulty of the ENARSI exam because they assume it’s simply a continuation of CCNA-level knowledge. However, the 300-410 exam demands a much deeper understanding of how different components interact. It’s not just about knowing how to configure something; it’s about understanding why it behaves the way it does in complex environments.
One common mistake is misinterpreting routing behaviors due to overlapping policies or redistribution loops. Without a solid grasp of protocol-specific nuances and route-map logic, even seasoned professionals can misdiagnose problems.
Another challenging area is the integration of security into routing decisions. Many candidates are unfamiliar with using CoPP, prefix-lists for control plane traffic, or understanding the implications of routing authentication across multi-vendor environments.
The exam also places significant weight on your ability to interpret output from multiple commands. You may not always have access to configurations; instead, you’re expected to deduce problems from show commands, debug outputs, or partial configurations.
A methodical approach is crucial for mastering the ENARSI exam. First, a solid foundation in CCNA routing concepts is assumed, so any gaps there must be resolved. Then, create a study plan that includes theory, labs, and real-world application.
Use labs daily to recreate exam scenarios. Focus especially on route redistribution, PBR, DMVPN, BGP policies, and OSPF area types. Use topology generators or lab guides that challenge your understanding rather than just walking through configurations.
Keep a command reference for troubleshooting and configuration. This could be a document or flashcard set covering commands like show ip protocols, show ip bgp, debug ip ospf events, and show crypto session. Knowing these by heart can save time and avoid errors during labs.
Lastly, don’t ignore documentation review. Exam simulations often mirror Cisco documentation syntax or best practices, especially in IPv6, DMVPN, or PBR scenarios. Being familiar with how Cisco documents present their technologies can help you interpret vague exam instructions more effectively.
Earning the 300-410 ENARSI certification is not just a mark of technical expertise—it is a reflection of real-world operational readiness in managing, securing, and troubleshooting enterprise-level networks. It serves as a powerful step beyond foundational knowledge, and it confirms your capability to handle complex routing scenarios, advanced VPN architectures, and high availability solutions across large, distributed systems.
This certification targets professionals who already understand the basics of networking and are now prepared to demonstrate deeper problem-solving skills under pressure. What makes ENARSI unique is its emphasis on operational command-line proficiency and your ability to isolate, troubleshoot, and resolve network issues in time-sensitive environments. Whether it’s manipulating BGP attributes, resolving OSPF adjacency failures, tuning EIGRP convergence, or debugging IPsec tunnels, this exam demands technical confidence and precise decision-making.
The practical depth of 300-410 means that rote memorization of commands will not suffice. Success depends on understanding how routing behaviors interact dynamically under different conditions. Candidates are often challenged by multi-protocol redistribution, recursive route resolution, and route filtering logic that simulates unpredictable enterprise changes. These complexities mirror the challenges faced by real-world network engineers responsible for resilient and high-performing infrastructures.
What sets apart ENARSI from other certification exams is its strong alignment with industry demand. Many organizations today seek network engineers who can not only implement protocols but also design scalable, secure, and redundant topologies that can evolve as business needs grow. From secure VPN deployments using DMVPN and IPsec to multicast routing for rich media distribution and WAN failover using advanced SLA tracking—every topic covered in the exam is practical and deployable in production networks.
Equally important is the troubleshooting aspect emphasized throughout the certification. You are expected to leverage show, debug, and verification tools confidently. This includes using packet capture, reviewing interface counters, understanding syslog output, or interpreting route maps and prefix-lists under live network changes. Your value as a certified engineer increases exponentially when you can isolate faults quickly, maintain service uptime, and apply logical steps to identify root causes with minimal disruption.
Preparation for the 300-410 exam is both rigorous and rewarding. It compels you to work through lab simulations repeatedly and refine your configurations until behavior is predictable. Using topology diagrams, building configurations from scratch, simulating link failures, and testing failovers are all critical parts of the preparation process. Additionally, developing muscle memory with IOS CLI commands while maintaining an analytical mindset gives you a significant edge on exam day.
Ultimately, the ENARSI certification empowers you with the confidence to take ownership of large-scale network environments. Whether you're transitioning into a senior role, aiming to become a specialist in routing and services, or paving the way toward network architecture roles, this exam solidifies your credibility. It is not just a test—it is a real-world benchmark of engineering depth that ensures you’re ready to tackle high-level responsibilities in modern enterprise networks.
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