Configuration parameters for AFM-based DR

The following table lists the AFM-based DR configuration parameters with their default values and the commands to set and edit the parameters:

Table 1. Configuration parameters at primary and their default values
AFM configuration parameter Unit Description Mode on AFM-DR
afmAsyncDelay Seconds Indicates the time at which the requests start flushing to the secondary cluster. For write-intensive applications that write to the same set of files, this delay is helpful because it replaces multiple writes to the secondary cluster with a single write containing the latest data. However, setting a very high value weakens the consistency of the data on the remote cluster. primary
afmDisconnectTimeout Seconds Defines the interval until which the primary gateway waits after it detects that the secondary cluster is inaccessible before declaring the outage by moving the primary cluster state to Disconnected. primary
afmEnableNFSSec - If enabled at primary, exported paths from secondary with kerberos-enabled security levels like sys, krb5, krb5i, krb5p are mounted at primary in the increasing order of security level - sys, krb5, krb5i, krb5p. For example, the security level of exported path is krb5i then at primary, AFM tries to mount with level sys, followed by krb5, and finally mounts with the security level krb5i. If disabled at primary, exported paths from secondary are mounted with security level sys at primary. You must configure KDC clients on all the gateway nodes at primary before enabling this parameter. primary
Start of changeafmHashVersionEnd of change Start of change End of change Start of changeStart of changeSpecifies the gateway node hashing algorithm that minimizes the impact of gateway nodes joining or leaving the active cluster by running as few recoveries as possible and balance mapping of AFM DR filesets across the gateway node. Valid values are 1,2,4, and 5. Default value is 2. You can specify the value by using mmchconfig. For example, to set the value 4, run mmchconfig afmHashVersion=4.End of changeEnd of change Start of changeNot applicableEnd of change
mountRetryInterval Seconds Specifies the interval after which the primary gateway retries an operation at secondary, in cases where the secondary is in an unhealthy state. Needs the GW node recycle or -i option for immediate effect. It is tunable per gateway. The updated value is visible only as long as the gateway is active and is applicable for all filesets owned by that gateway. primary
afmRPO Minutes, hours, weeks Specifies the interval for generating RPO snapshots. primary
afmAsyncOpWaitTimeout seconds Specifies the time that AFM DR waits for completion of any inflight asynchronous operation which is synchronizing with the primary. Subsequently, AFM DR cancels the operation and synchronizes again after primary is available. primary
afmSyncOpWaitTimeout seconds Specifies the time that AFM DR waits for completion of any inflight synchronous operation which is synchronizing with the primary. When any application is performing any synchronous operation at primary, AFM DR tries to get a response from primary. If primary is not responding, application might be unresponsive. If operation does not complete in this timeout interval, AFM DR cancels the operation. primary
Table 2. Configuration parameters at primary and their default values - Valid values
AFM configuration parameter Valid values Default value Tunable at the cluster level Tunable at the fileset level
afmAsyncDelay 1 - 2147483647 15 Yes Yes
afmDisconnectTimeout 0 - 2147483647, disable 60 Yes No
afmEnableNFSSec Yes | No No Yes No
Start of changeafmHashVersionEnd of change Start of change1 | 2 | 4Start of change| 5End of changeEnd of change Start of change2End of change Start of changeYesEnd of change Start of changeNoEnd of change
mountRetryInterval   300 No No
afmRPO 720 - 2147483647 disabled No Yes
afmAsyncOpWaitTimeout 5 - 2147483647 300 Yes No
afmSyncOpWaitTimeout 5 - 2147483647 180 Yes No