doc/rbd: Improve nvmeof-requirements.rst with proxy and other info

Signed-off-by: Anthony D'Atri <anthonyeleven@users.noreply.github.com>

diff --git a/doc/rbd/nvmeof-requirements.rst b/doc/rbd/nvmeof-requirements.rst
index 0bbb80f1dcb85cac771f96a58aa676be83ecd36d..72a88b316818b93f010e2a2dee2b2115ade7f7be 100644 (file)
--- a/doc/rbd/nvmeof-requirements.rst
+++ b/doc/rbd/nvmeof-requirements.rst
@@ -1,10 +1,29 @@
 ============================
-NVME-oF Gateway Requirements
+NVMe-oF Gateway Requirements
 ============================
 
-- At least 8 GB of RAM dedicated to the GW  (on each node running an NVME-oF GW) 
-- It is hightly recommended to dedicate at least 4 cores to the GW (1 can work but perofrmance will be accordingly) 
-- For high availability, provision at least 2 GWs in a GW group. 
-- A minimum a single 10Gb Ethernet link in the Ceph public network for the gateway. For higher performance use 25 or 100 Gb links in the public network. 
-- Provision at least two NVMe/TCP gateways on different Ceph nodes for highly-availability Ceph NVMe/TCP solution. 
+- At least 8 GB of RAM dedicated to each gateway instance
+- It is hightly recommended to dedicate at least four CPU threads / vcores to each
+  gateway.  One can work but performance may be below expectations.  It is
+  ideal to dedicate servers to NVMe-oF gateway service so that these
+  and other Ceph services do not degrade each other.
+- At minimum a 10 Gb/s network link to the Ceph public network. For best
+  latency and throughput we recommend 25 Gb/s or 100 Gb/s links.
+- Bonding of network links, with an appropriate xmit hash policy, is ideal
+  for high availability.  Note that the throughput of a given NVMe-oF client
+  can be no higher than that of a single link within a bond.  Thus, if four
+  10 Gb/s links are bonded together on gateway nodes, no one client will
+  realize more than 10 Gb/s throughput.  Moreover, remember that Ceph
+  NVMe-oF gateways also communicate with backing OSDs over the public
+  network at the same time, which contends with traffic between clients
+  and gateways. Provision networking generously to avoid congestion and
+  saturation.
+- Provision at least two NVMe-oF gateways in a gateway group, on separate
+  Ceph cluster nodes, for a highly-availability Ceph NVMe/TCP solution.
+- Ceph NVMe-oF gateway containers comprise multiple components that communicate
+  with each other.  If the nodes running these containers require HTTP/HTTPS
+  proxy configuration to reach container registries or other external resources,
+  these settings may confound this internal communication.  If you experience
+  gRPC or other errors when provisioning NVMe-oF gateways, you may need to
+  adjust your proxy configuration.