The Network Firewall Manager (NFM) provides stateful, layer 3/4 firewall capabilities that are ideal for creating and enforcing security policies between network segments or zones, such as a DMZ and an internal network. It allows for granular rule-based control over traffic flow, which is the core requirement for inspecting and controlling traffic between the web and database tiers.

The BIG-IP negotiates SSL/TLS ciphers by presenting its ordered list to the client. The client selects the first cipher it supports from that list. If the first cipher in the ‘DEFAULT’ list is not supported by a particular client (e.g., an older browser or device), the handshake will fail. Intermittent failures point to client variability, making this the most likely cause.

HA Groups allow administrators to define specific criteria (like the number of active connections on a pool) that trigger failover for a select group of traffic objects (like virtual servers). This provides granular control, allowing failover for critical applications while leaving less critical services unaffected by a partial system issue, perfectly matching the requirement.

A Local Traffic Policy (LTM Policy) is designed for this exact purpose: making content-switching decisions based on HTTP criteria (like URI). It is more efficient to process and manage at scale than an iRule for simple path-based routing, and it provides a clear, visual rule configuration within the GUI. It cleanly separates the logic for `/api/health` from the default pool.

Advanced health monitors (like HTTP or HTTPS) can be configured with specific send and receive strings. If the monitor is configured to check `/app/status` and that specific endpoint is failing (e.g., returning a 500 error or an unexpected string), the monitor will mark the node down. The main application page (`/`) might still be functional, leading to the observed discrepancy.

A high connection count with low throughput suggests that many connections are open but not actively transferring large amounts of data. This is characteristic of applications that use many small, frequent requests (chatty APIs) or maintain long-lived, idle connections (like web sockets or some real-time applications), as opposed to bulk data transfer sessions which would have high throughput per connection.

SNAT (Secure Network Address Translation) is specifically designed to translate the source IP of connections initiated by the BIG-IP itself. By creating a SNAT pool (with one or more translation addresses) and referencing it in the configuration of a health monitor or within an iRule using the `snatpool` command, you can ensure all traffic originating from the BIG-IP uses the mandated source IP.

GTM/BIG-IP DNS performs its own independent health monitoring of the resources (like LTM virtual servers) it is load balancing across. This is configured by defining a probe (e.g., TCP, HTTP, ICMP) on the GTM system itself. It does not solely rely on LTM’s internal pool status; it actively verifies reachability from the DNS perspective, which is crucial for accurate global server load balancing (GSLB) decisions.

Connection multiplexing via OneConnect works by maintaining a separate, server-side connection pool. If Source Address persistence is enabled, the BIG-IP must send all requests from a given client IP to the same pool member. This often prevents the efficient reuse of server-side connections across different clients, defeating the purpose of OneConnect. Disabling persistence (or using a compatible type like cookie persistence) is typically required for OneConnect to function effectively.

The Network Firewall Manager (NFM) provides stateful, layer 3/4 firewall capabilities that are ideal for creating and enforcing security policies between network segments or zones, such as a DMZ and an internal network. It allows for granular rule-based control over traffic flow, which is the core requirement for inspecting and controlling traffic between the web and database tiers.0