Use OpenVPN split tunneling when users need secure access to private apps without forcing every website, video call, and update through the VPN. Use a full tunnel when you need tighter inspection, logging, or policy control over all traffic. For many teams, the best long-term answer is neither one alone, but a move toward Zero Trust Network Access, or ZTNA, for app-level access.
TLDR: Split tunneling sends only selected traffic through OpenVPN, while a full tunnel sends everything through it. For example, a 300-person company may cut VPN bandwidth by 60% if Microsoft 365, Zoom, and general browsing go directly to the internet. Full tunneling gives stronger centralized control, but it can slow users down and overload VPN gateways. ZTNA is often cleaner because users connect to specific apps, not the whole network.
What OpenVPN Split Tunneling Actually Does
OpenVPN split tunneling separates traffic into two paths. Traffic meant for company resources goes through the encrypted VPN tunnel. Everything else goes out through the user’s normal internet connection.
For example, a remote worker may access an internal Git server at 10.10.20.15 through OpenVPN. At the same time, their YouTube music, Gmail, Slack, or software updates go straight to the internet. The VPN does not carry those packets.
This sounds simple, but the routing rules matter. Split tunneling depends on correct configuration of routes, DNS, firewall rules, and client settings. One bad route can send too much traffic through the tunnel. One missing DNS rule can make internal apps fail in weird ways. Honestly, it feels like VPN troubleshooting always starts with someone saying, “It worked yesterday.”
Split Tunnel vs Full Tunnel
A full tunnel forces all user traffic through the VPN. Web browsing, SaaS apps, file downloads, updates, and internal systems all travel through the corporate VPN gateway first.
A split tunnel sends only selected traffic through the VPN. Usually this means internal IP ranges, private DNS zones, or specific business systems.
| Feature | Split Tunnel | Full Tunnel |
|---|---|---|
| Performance | Usually faster for internet apps | Can be slower due to VPN gateway load |
| Security control | More limited outside VPN traffic | Stronger central monitoring |
| Bandwidth use | Lower | Higher |
| User experience | Better for video calls and SaaS | Can add latency |
| Admin effort | Needs careful route planning | Simpler concept, heavier infrastructure |
Why Teams Choose Split Tunneling
The big reason is performance. Sending all traffic through one VPN hub can create a traffic jam. If hundreds of users join video meetings, sync cloud storage, and download patches through the VPN, the gateway becomes a choke point.
Split tunneling also saves money. Less VPN traffic means fewer gateway resources, less cloud egress, and fewer emergency upgrades. It can also make users happier. A 40 ms SaaS connection may become 120 ms or worse when dragged through a full tunnel in another region. That extra delay does not sound huge until every page feels sticky.
Common split tunnel use cases include:
- Remote access to internal apps: ERP systems, intranet tools, admin panels, Git servers, and databases.
- Cloud-heavy companies: Teams using Google Workspace, Microsoft 365, Salesforce, Zoom, and similar services.
- Global staff: Users located far from the main VPN gateway.
- BYOD access: Limited access from personal devices, with strict routes and policies.
The Security Tradeoff
The catch is that split tunneling creates two active paths. One goes to the trusted network. The other goes straight to the internet. If the endpoint is infected, an attacker may use the VPN path to reach private systems while using the direct internet path for command traffic.
That does not mean split tunneling is unsafe by default. It means endpoint security matters. So do access controls. A flat internal network paired with split tunneling is asking for trouble. A segmented network with MFA, device checks, DNS filtering, EDR, and tight firewall rules is much safer.
Good split tunnel security should include:
- Multi-factor authentication for all VPN users.
- Least privilege access based on role and device status.
- Endpoint protection with patch checks and malware detection.
- DNS controls to stop leaks and block known bad domains.
- Logging for VPN sessions, internal access, and policy failures.
When Full Tunnel Still Makes Sense
Full tunneling is still useful. Some industries need central inspection for compliance. Legal, finance, healthcare, and government teams may need complete web logs or strict filtering for every user session.
It also helps when users work from risky networks. Hotels, airports, cafés, and shared apartments can expose traffic to tampering. A full tunnel adds a consistent protection layer, especially when paired with secure web gateways and traffic inspection.
Full tunnel works best when companies have enough infrastructure. That means VPN gateways near users, strong bandwidth planning, and monitoring that proves the system can handle peak hours. Without that, expect complaints. “The VPN is slow” becomes the soundtrack of the help desk.
OpenVPN Split Tunnel Configuration Basics
OpenVPN split tunneling usually comes down to routing. Admins decide which networks should go through the tunnel and which should not.
A split tunnel setup may push routes like:
10.0.0.0/8for internal private systems172.16.0.0/12for data center resources192.168.50.0/24for a specific office subnet
In a full tunnel setup, OpenVPN often pushes a default route. That tells the client to send nearly all traffic through the VPN.
DNS also needs care. If internal apps use names like crm.internal.company, clients must know which DNS server can resolve them. Split DNS can help. It sends internal name lookups to corporate DNS while public domains use normal resolvers.
Common mistakes include overlapping home network ranges, missing return routes, public DNS breaking internal names, and users gaining access to more subnets than they need. The annoying part is that these issues often look like random app failures, not routing problems.
Where ZTNA Fits
ZTNA changes the model. Instead of connecting a user to a network, it connects a verified user to a specific application. The user does not get broad subnet access just because the VPN is connected.
With ZTNA, access decisions can use identity, device health, location, risk score, app sensitivity, and session behavior. A contractor may get access to one ticketing system. A developer may get access to a staging app. Neither needs visibility into the whole private network.
This is why many teams see ZTNA as a better match for modern work. Apps are spread across data centers, clouds, and SaaS platforms. Users are everywhere. Devices vary. A network-level tunnel can feel blunt.
OpenVPN vs ZTNA: Which Should You Pick?
Choose OpenVPN split tunneling if you need a practical fix for bandwidth, latency, and remote access to private subnets. It is familiar, flexible, and cost-effective. It works well when configured with strict access rules.
Choose OpenVPN full tunneling if you need all traffic inspected or logged through corporate security tools. It is better for centralized control, but it needs more capacity and better planning.
Choose ZTNA if your goal is app-level access with less network exposure. It is especially strong for contractors, hybrid cloud apps, mergers, and teams that want to reduce VPN risk over time.
Many companies use a mix. They keep OpenVPN for admin access, legacy apps, or server maintenance. Then they move common business apps to ZTNA. That hybrid path is often easier than ripping out VPN access overnight.
Best Practice Recommendation
Start with the risk profile. Do not pick split tunnel just because it is faster. Do not pick full tunnel just because it sounds safer. Map users, apps, data sensitivity, and traffic volume.
For most mid-sized teams, the smartest setup is:
- Split tunnel OpenVPN for trusted employees who need private network access.
- Full tunnel VPN for high-risk users, regulated workflows, or unmanaged networks.
- ZTNA for app-specific access and third-party users.
- Continuous monitoring so access rules do not rot over time.
The best remote access design is not the one with the most control on paper. It is the one that protects sensitive systems, keeps users productive, and does not collapse every Monday at 9:05 a.m.
