Be sure to review the NIC support information carefully before making any NIC purchases.
Which NIC driver to use
If only possible, we strongly recommend that you use custom drivers, for the L size NAM Probe in particular. NAM Probe performance may be up to two times better with custom drivers. See NAM Probe capacity estimates for details.
Custom drivers - pros and cons
- Provide superior performance in packet filtering and processing due to custom designed data acquisition techniques.
- Provide hardware-based load balancing performed by the card itself, improving the overall performance of the NAM Probe. In fact, hardware-based load balancing is a must for traffic profiles exceeding the 10 Gbps capacity.
- Provide additional driver and NIC statistics available through the rcon and NAM Console which are helpful in port mirroring troubleshooting.
- In terms of the driver, it does not matter whether the card is fiber or copper.
- Available for a relatively small subset of NIC cards.
- rcon based nfdump captures only configuration filtered packets.
Native drivers - pros and cons
- Can be used with majority of cards available on the market, including cards not tested by Dynatrace.
- Are provided with Red Hat distribution, and require no additional installation steps.
- Decreased (up to 50% in some cases) performance in data filtering and processing.
- Increased CPU load during filtering even though the analyzed traffic might be of low volume
- Load balancing feature is not supported.
- Partial rcon and NAM Console statistics pertaining to the driver and NIC.
- Sudden large traffic peaks or performance drops for any reason (such as a deadlock in an analyzer) may cause the native driver RTM to run out of memory and crash. In custom driver mode, this will just result in extensive dropping.
Be aware that some vendors offer cards that are similar to cards we recommend, but that are still incompatible with the custom driver. If you are considering using a card that has not been tested, be sure to contact Support first.
For more information, see Hardware Recommendations.
Ensuring NIC driver compatibility
When selecting NICs for a NAM Probe, be sure to follow these rules:
- Two cards are compatible if they can use the same custom driver. Check the tables to see which custom driver each card takes.
- You cannot mix custom and native drivers on the same NAM Probe.
- You cannot mix different custom drivers in the same NAM Probe.
- You can mix unsupported NICs with supported NICs as long as they all use the native driver.
- You cannot mix 1 GbE sniffing NICs with 10 GbE.
Testing other cards
We have tested the cards as listed in NICs Tested by Dynatrace. We make no warranty, implied or otherwise, regarding any other card's performance or reliability.
If you are thinking about trying untested cards, you must make sure:
- Your deployment adheres to the NIC driver compatibility rules described above.
- Your card uses an ixgbe or i40 driver.
Before testing other cards, be sure to see NIC testing in the community for essential additional information.