iSCSI Gateway Requirements¶
To implement the Ceph iSCSI gateway there are a few requirements. It is recommended to use two to four iSCSI gateway nodes for a highly available Ceph iSCSI gateway solution.
For hardware recommendations, see Hardware Recommendations for more details.
Note
On the iSCSI gateway nodes, the memory footprint of the RBD images can grow to a large size. Plan memory requirements accordingly based off the number RBD images mapped.
There are no specific iSCSI gateway options for the Ceph Monitors or OSDs, but it is important to lower the default timers for detecting down OSDs to reduce the possibility of initiator timeouts. The following configuration options are suggested for each OSD node in the storage cluster:
[osd]
osd heartbeat grace = 20
osd heartbeat interval = 5
Online Updating Using the Ceph Monitor
ceph tell <daemon_type>.<id> config set <parameter_name> <new_value>
ceph tell osd.0 config set osd_heartbeat_grace 20 ceph tell osd.0 config set osd_heartbeat_interval 5
Online Updating on the OSD Node
ceph daemon <daemon_type>.<id> config set osd_client_watch_timeout 15
ceph daemon osd.0 config set osd_heartbeat_grace 20 ceph daemon osd.0 config set osd_heartbeat_interval 5
For more details on setting Ceph’s configuration options, see Configuring Ceph.