AWS sap documentation change
Summary
Added steps to configure NFS client parameters for faster failover detection and reduced I/O errors during FSx for ONTAP failovers, including planned maintenance
Security assessment
The changes optimize NFS client behavior for reliability during failovers but do not address specific security vulnerabilities. Focus is on preventing operational disruptions and emergency shutdowns rather than security threats.
Diff
diff --git a/sap/latest/sap-hana/fsx-host-scaleout.md b/sap/latest/sap-hana/fsx-host-scaleout.md index 05e972e24..772b62768 100644 --- a//sap/latest/sap-hana/fsx-host-scaleout.md +++ b//sap/latest/sap-hana/fsx-host-scaleout.md @@ -36,2 +36 @@ The following section is an example host setup for SAP HANA scale-out with stand -Create a file named `91-NetApp-HANA.conf` with the following configurations in the `/etc/sysctl.d` directory on all the nodes. - + 1. Create a file `/etc/sysctl.d/91-NetApp-HANA.conf` with the following configurations @@ -49,0 +49,12 @@ Create a file named `91-NetApp-HANA.conf` with the following configurations in t + sunrpc.tcp_slot_table_entries = 128 + + 2. To reduce I/O errors during failover of FSx for ONTAP Single-AZ file systems, including [planned maintenance windows](https://docs.aws.amazon.com/fsx/latest/ONTAPGuide/maintenance-windows.html) create an additional file `/etc/sysctl.d/99-fsx-failover.conf`. These parameters optimize NFS client behavior to detect and respond to failover events more quickly. + + # NFS client optimizations for faster failover detection + # Replace 'default' with your interface name (e.g., eth0, ens5) to target a specific interface + net.ipv4.neigh.default.base_reachable_time_ms = 5000 + net.ipv4.neigh.default.delay_first_probe_time = 1 + net.ipv4.neigh.default.ucast_solicit = 0 + net.ipv4.tcp_syn_retries = 3 + +For more information and options, see [Troubleshooting I/O errors and NFS lock reclaim failures](https://docs.aws.amazon.com/fsx/latest/ONTAPGuide/nfs-failover-issues.html). @@ -51 +62 @@ Create a file named `91-NetApp-HANA.conf` with the following configurations in t -Increase the max sessions slots for NFSv4 to 180. +If these errors occur, in some cases they may cause SAP HANA to perform an emergency shutdown of the indexserver process to protect database consistency. @@ -52,0 +64 @@ Increase the max sessions slots for NFSv4 to 180. + 3. Increase the max sessions slots for NFSv4 to 180. @@ -56 +68,4 @@ Increase the max sessions slots for NFSv4 to 180. -You must reboot your instance for the kernel parameters and NFS settings to take effect. + + + +To activate these changes, run `sysctl -p` for the kernel parameters and reload the NFS module, or reboot the instance during a planned maintenance window (recommended).