Database Reference
In-Depth Information
is easily achievable in an existing network environment.
Caution
Some network device vendors, such as Arista, ship their equipment from the
factory with jumbo frames enabled. However, other vendors and some older
network devices, if not properly configured, may not allow jumbo frames to pass
and will simply drop the packets instead of fragmenting them. Some devices will
break the packets down to a smaller size (fragment the packets) and allow them to
pass, but the cost of breaking the packets down will severely slow down your
network. Some network devices may only allow jumbo frames to be set globally,
and the settings may only take effect after a reboot. Because of this, it is important
that you check the support of jumbo frames on your network devices with your
vendor and have a thorough implementation and test plan to ensure desired
results.
The types of network traffic that will benefit most from using jumbo frames on 10Gbps
and above networks include SQL Database Mirroring, Log Shipping, AlwaysOn
Availability Groups, Backup Traffic, VMware vMotion (including Multi-NIC
vMotion), and IP-based storage, such as iSCSI and NFS. In order for SQL Server to use
jumbo frames effectively, the Network Packet Size Advanced option should be
increased from its default setting. This is in addition to configuring jumbo frames in
Windows and on the virtual and physical networks. The Network Packet Size setting
should be increased from its default value of 4096 to 8192, as shown in
Figure 8.6
.
