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Address comments from @EFM-Bobby
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- Ambiguity around phrasing for agent shutdown
- Ambiguity around phrasing for VIP assignment during promotion
- other inaccuracies
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josh-heyer authored Nov 2, 2023
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Expand Up @@ -23,9 +23,9 @@ This allows you to upgrade and perform maintenance on EFM services without inter

## Behavior during promotion of a node from standby to primary

The VIP should be initially assigned to the primary node. When EFM detects failure of the primary node, it will release the VIP and then assign it to a standby node as that node is promoted to be the new primary.
The VIP should be initially assigned to the primary node. When EFM detects failure of the primary node's database, it will release the VIP and then assign it to a standby node as that node is promoted to be the new primary.

EFM verifies (via the command configured via the [`ping.server.command`](01_cluster_properties.mdx#ping_server_command) cluster property) that the VIP is not currently in use during promotion of a standby, and will skip assigning it to the new primary node if it is already assigned. This behavior can be disabled via the [`check.vip.before.promotion`](01_cluster_properties.mdx#check_vip_before_promotion) cluster property.
EFM verifies (via the command configured via the [`ping.server.command`](01_cluster_properties.mdx#ping_server_command) cluster property) that the VIP is not currently in use during promotion of a standby, and will not assign it to the new primary node until the ping indicates it is unreachable. You can disable this behavior via the [`check.vip.before.promotion`](01_cluster_properties.mdx#check_vip_before_promotion) cluster property.

!!!tip "Meaning of the ping command exit code"
Failover Manager uses the exit code of the ping command to determine whether an address is reachable. A zero exit code indicates the address is reachable (in this context, this means the VIP is assigned). A non-zero exit code indicates the address isn't reachable (in this context, this means the VIP is unassigned).
Expand All @@ -46,9 +46,7 @@ If the VIP uses a different interface from the `bind.address`, you might encount

Failover Manager uses the `efm_address` script to assign or release a virtual IP address.

By default, the script resides in:

`/usr/edb/efm-4.<x>/bin/efm_address`
The script resides in: `/usr/edb/efm-4.<x>/bin/efm_address`

Failover Manager uses the following command variations to assign or release an IPv4 or IPv6 IP address.

Expand Down Expand Up @@ -158,7 +156,7 @@ When instructed to ping the VIP from a node, use the command defined by the [`pi
...
```

The output from this step doesn't show an eth0 interface.
The output from this step will no longer show the VIP address on the eth0 interface.

5. Repeat step 3, this time verifying that the standby and witness don't see the VIP in use:

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