Add a new REST ISCSISession template

[cgrinds]

Note: These steps are for NABox.

Prerequisite: ssh to NABox via root

Step 1: Create custom_iscsi.yaml

Navigate to the rest directory:

cd /opt/harvest2-conf/conf/rest

Create custom_iscsi.yaml:

vi custom_iscsi.yaml

Update the file with the following content:

objects:
  ISCSISession:
    - iscsi_session.yaml

Step 2: Create iscsi_session.yaml

Navigate to the 9.6.0 directory:

cd /opt/harvest2-conf/conf/rest/9.6.0

Create iscsi_session.yaml:

vi iscsi_session.yaml

Update the file with the following content:

name:               ISCSISession
query:              api/protocols/san/iscsi/sessions
object:             iscsi_session

counters:
  - ^^connections.#.initiator_address.address => initiator_address
  - ^^initiator.name                          => initiator
  - ^^tsih                                    => tsih
  - ^svm.name                                 => svm

plugins:
  - LabelAgent:
      split_regex:
        - initiator `:(.*?)(:|$)` host,

export_options:
  instance_keys:
    - initiator
    - initiator_address
    - tsih
  instance_labels:
    - host
    - svm

Step 3: Restart NABox containers

dc restart

Step 4: Validate ISCSISession Collection in Harvest

Wait for at least 1 minute. To ensure that the Rest:ISCSISession metrics are being collected, run the following command:

dc logs nabox-harvest2 | grep -w 'Rest:ISCSISession'

In the screenshot below, you can see that the poller pstejska_vsim is collecting Rest:ISCSISession instances.

Step 5: Verify ISCSISession Metrics are in Prometheus

Confirm that the ISCSISession metrics are being scraped by Prometheus by running the following query from Prometheus (https://NABox/prometheus):

iscsi_session_labels

[chuan137]

This is great, thank you for working this out. I just see many warnings like,

2024-01-31T07:54:11Z WRN rest/rest.go:495 > This instance is already processed. instKey is not unique Poller=stnpca1-bb091 collector=Rest:ISCSISession instKey="iqn.1998-01.com.vmware:node003-bb092-53e3b8e2[\"10.46.69.134\"]"

I think for same initiator, only one tsih is processed. For our use case, it might be ok. But I guess it would be nicer to poll all the session ids. Otherwise it might be confusing.

[rahulguptajss]

@chuan137 See if below template fixes warnings.

name:               ISCSISession
query:              api/protocols/san/iscsi/sessions
object:             iscsi_session

counters:
  - ^^connections.#.initiator_address.address => initiator_address
  - ^^initiator.name                          => initiator
  - ^^tsih                                    => tsih
  - ^svm.name                                 => svm

export_options:
  instance_keys:
    - initiator
    - initiator_address
    - tsih
  instance_labels:
    - svm

[chuan137]

this has fixed the warnings, thank you @rahulguptajs

[chuan137]

discussed on the discord, I would like also to split the initiator address to get only the hostname
can you iterate on that pls?

[rahulguptajss]

@chuan137 See if below works.

name:               ISCSISession
query:              api/protocols/san/iscsi/sessions
object:             iscsi_session

counters:
  - ^^connections.#.initiator_address.address => initiator_address
  - ^^initiator.name                          => initiator
  - ^^tsih                                    => tsih
  - ^svm.name                                 => svm

plugins:
  - LabelAgent:
      split_regex:
        - initiator `:(.*?):` host

export_options:
  instance_keys:
    - initiator
    - initiator_address
    - tsih
  instance_labels:
    - host
    - svm

[rahulguptajss]

@chuan137 I have updated the regex in the template below to accommodate other naming conventions for the initiator name.
Tested with below patterns

iqn.1991-05.com.microsoft:abc.netapp.com
iqn.1998-01.com.vmware:abc.netapp.com:1258008586:64

name:               ISCSISession
query:              api/protocols/san/iscsi/sessions
object:             iscsi_session

counters:
  - ^^connections.#.initiator_address.address => initiator_address
  - ^^initiator.name                          => initiator
  - ^^tsih                                    => tsih
  - ^svm.name                                 => svm

plugins:
  - LabelAgent:
      split_regex:
        - initiator `:(.*?)(:|$)` host,

export_options:
  instance_keys:
    - initiator
    - initiator_address
    - tsih
  instance_labels:
    - host
    - svm

[chuan137]

yes, the updated regex works better. Why is there a comma after host?

[chuan137]

besides, looks like host should be added to the counters as well?

[rahulguptajss]

The comma after host is used to ignore any text following the second :. counters is something we obtain from ONTAP. The host variable is a derived field, generated by the split_regex plugin.

[rahulguptajss]

More information about split_regex plugin is available here