Appendix B. Ceph network configuration options
These are the common network configuration options for Ceph.
public_network- Description
-
The IP address and netmask of the public (front-side) network (for example,
192.168.0.0/24). Set in[global]. You can specify comma-delimited subnets. - Type
-
<ip-address>/<netmask> [, <ip-address>/<netmask>] - Required
- No
- Default
- N/A
public_addr- Description
- The IP address for the public (front-side) network. Set for each daemon.
- Type
- IP Address
- Required
- No
- Default
- N/A
cluster_network- Description
-
The IP address and netmask of the cluster network (for example,
10.0.0.0/24). Set in[global]. You can specify comma-delimited subnets. - Type
-
<ip-address>/<netmask> [, <ip-address>/<netmask>] - Required
- No
- Default
- N/A
cluster_addr- Description
- The IP address for the cluster network. Set for each daemon.
- Type
- Address
- Required
- No
- Default
- N/A
ms_type- Description
-
The messenger type for the network transport layer. Red Hat supports the
simpleand theasyncmessenger type usingposixsemantics. - Type
- String.
- Required
- No.
- Default
-
async+posix
ms_public_type- Description
-
The messenger type for the network transport layer of the public network. It operates identically to
ms_type, but is applicable only to the public or front-side network. This setting enables Ceph to use a different messenger type for the public or front-side and cluster or back-side networks. - Type
- String.
- Required
- No.
- Default
- None.
ms_cluster_type- Description
-
The messenger type for the network transport layer of the cluster network. It operates identically to
ms_type, but is applicable only to the cluster or back-side network. This setting enables Ceph to use a different messenger type for the public or front-side and cluster or back-side networks. - Type
- String.
- Required
- No.
- Default
- None.
Host options
You must declare at least one Ceph Monitor in the Ceph configuration file, with a mon addr setting under each declared monitor. Ceph expects a host setting under each declared monitor, metadata server and OSD in the Ceph configuration file.
Important
Do not use localhost. Use the short name of the node, not the fully-qualified domain name (FQDN). Do not specify any value for host when using a third party deployment system that retrieves the node name for you.
mon_addr- Description
-
A list of
<hostname>:<port>entries that clients can use to connect to a Ceph monitor. If not set, Ceph searches[mon.*]sections. - Type
- String
- Required
- No
- Default
- N/A
host- Description
-
The host name. Use this setting for specific daemon instances (for example,
[osd.0]). - Type
- String
- Required
- Yes, for daemon instances.
- Default
-
localhost
TCP options
Ceph disables TCP buffering by default.
ms_tcp_nodelay- Description
-
Ceph enables
ms_tcp_nodelayso that each request is sent immediately (no buffering). Disabling Nagle’s algorithm increases network traffic, which can introduce congestion. If you experience large numbers of small packets, you may try disablingms_tcp_nodelay, but be aware that disabling it will generally increase latency. - Type
- Boolean
- Required
- No
- Default
-
true
ms_tcp_rcvbuf- Description
- The size of the socket buffer on the receiving end of a network connection. Disabled by default.
- Type
- 32-bit Integer
- Required
- No
- Default
-
0
ms_tcp_read_timeout- Description
-
If a client or daemon makes a request to another Ceph daemon and does not drop an unused connection, the
tcp read timeoutdefines the connection as idle after the specified number of seconds. - Type
- Unsigned 64-bit Integer
- Required
- No
- Default
-
90015 minutes.
Bind options
The bind options configure the default port ranges for the Ceph OSD daemons. The default range is 6800:7100. You can also enable Ceph daemons to bind to IPv6 addresses.
Important
Verify that the firewall configuration allows you to use the configured port range.
ms_bind_port_min- Description
- The minimum port number to which an OSD daemon will bind.
- Type
- 32-bit Integer
- Default
-
6800 - Required
- No
ms_bind_port_max- Description
- The maximum port number to which an OSD daemon will bind.
- Type
- 32-bit Integer
- Default
-
7300 - Required
- No.
ms_bind_ipv6- Description
- Enables Ceph daemons to bind to IPv6 addresses.
- Type
- Boolean
- Default
-
false - Required
- No
Asynchronous messenger options
These Ceph messenger options configure the behavior of AsyncMessenger.
ms_async_transport_type- Description
-
Transport type used by the
AsyncMessenger. Red Hat supports theposixsetting, but does not support thedpdkorrdmasettings at this time. POSIX uses standard TCP/IP networking and is the default value. Other transport types are experimental and are NOT supported. - Type
- String
- Required
- No
- Default
-
posix
ms_async_op_threads- Description
-
Initial number of worker threads used by each
AsyncMessengerinstance. This configuration setting SHOULD equal the number of replicas or erasure code chunks, but it may be set lower if the CPU core count is low or the number of OSDs on a single server is high. - Type
- 64-bit Unsigned Integer
- Required
- No
- Default
-
3
ms_async_max_op_threads- Description
-
The maximum number of worker threads used by each
AsyncMessengerinstance. Set to lower values if the OSD host has limited CPU count, and increase if Ceph is underutilizing CPUs are underutilized. - Type
- 64-bit Unsigned Integer
- Required
- No
- Default
-
5
ms_async_set_affinity- Description
-
Set to
trueto bindAsyncMessengerworkers to particular CPU cores. - Type
- Boolean
- Required
- No
- Default
-
true
ms_async_affinity_cores- Description
-
When
ms_async_set_affinityistrue, this string specifies howAsyncMessengerworkers are bound to CPU cores. For example,0,2will bind workers #1 and #2 to CPU cores #0 and #2, respectively. NOTE: When manually setting affinity, make sure to not assign workers to virtual CPUs created as an effect of hyper threading or similar technology, because they are slower than physical CPU cores. - Type
- String
- Required
- No
- Default
-
(empty)
ms_async_send_inline- Description
-
Send messages directly from the thread that generated them instead of queuing and sending from the
AsyncMessengerthread. This option is known to decrease performance on systems with a lot of CPU cores, so it’s disabled by default. - Type
- Boolean
- Required
- No
- Default
-
false
