Alletra MP - Some questions about replication

[IMPI-Ced]

Hi,

with your advices, i was able to configure synced replication between two Alletra

I have some concern about that :

  -1-  When doing a "Replication Partner System", i'm asked for an IP. I put the management one, all seems ok, is that the correct way ?

  -2- We put one IP per RCIP Port (8 : 2 Alletra x 2 nodes x 2 ports, all in the same subnet)

  -3- We created on both Alletra a user "replication" to  use  for replication (do not want to use admin!!) What rôle should we give ? "Service" is not enough then we gave "super" and it was ok, but isn't it too much ?

 -4- About MTU : we will have a synced replication between two Alletra and an asynced replication on a remote site. As a consequence we where obliged to set MTU to 1280 in order to be OK into the site-to-site VPN, but then MTU will be also set to 1280 for local replication, not really good. I guess i could use only ports 3 for local replication using MTU 9000 and ports 4 for remote replication using MTU 1280, but then i'll "only" have 10 Gbp between Alletra. Do i misunderstood something ? Any advice would be appreciated.

  -5- About Quorum witness : where can i find it ? I only find the 9000 or 3PAR version and then i'm not autorised to download it (I provided my Passport account with Alletra serial)

  -6- Is it possible to put the Quorum Witness on a Raspberry on something light ?

Two more question, not related :

  - The two Alletra are very noisy, and unlike Proliant they do not slow down nor regulate the fans, is that normal ?

  - Alletra system between nodes is active/passive, right ?

Many thanks for your help, have de nice day

Ced

[buzzsubash · Accepted solution]

1. That is correct, it has to be the management IP for the replication partner.

2. Should be good.

3. I think this is the only option available for now. We may consider creating an RFE request for consideration. However, there is no guarantee that it will be implemented.

4.  Have you considered an additional subnet to enable jumbo frames for local sync-rep replication? Please do create a support case to perform few tests before suggesting a solution.

5. It can be downloaded from Infosight by navigating to https://infosight.hpe.com/org/9bd869a0-0e12-4e2e-91c0-6da98aa1b082/resources/nimble/software/NimbleOS/Synchronous%20Replication%20Witness. 

6. Enterprise Linux 8 is supported (RHEL 8.x or compatible, qualified on Alma Linux 8.10 and Rocky Linux 8.5) when using version 6.1.2.500 of the witness. Configure the Linux firewall to allow traffic on 5395.

7. Yes, it is normal, Alletra fans are bit noisy compared to other models. I remember there is a bug around iLO firmware, but it is relevant for 6010 models changing to high speed in normal temperatures every few minutes. It can be ignored if there is no intermittent spike in the fan noise/speed.

8. That is correct, it is active/standby for iSCSi. Only for FC arrays running HPE Nimble OS 6.1.x+ does support bifrost(port forwarding) using active/active paths.

[IMPI-Ced]

Hi Subash,

really many thanks for such a great reply !

I still can not access to the link, but my Alletra (under testing period) were off for some weeks, and it seems they are not registered anymore on greenlake, maybe this is the problem. I'll open a case about that.

great idea to have subnet to have other MTU, i'll also open a case as per your advices, many thanks

Have a nice week-end

Ced

[veeyarvi]

Hi Ced,

For the below questions:

  - The two Alletra are very noisy, and unlike Proliant they do not slow down nor regulate the fans, is that normal ?  >> The Fan speed control is improved from 10.4.0 versions. If you are on 10.4.0 and still issues, please log a case with the support.

  - Alletra system between nodes is active/passive, right ? Yes

Regards,
Veeyaarvi

[IMPI-Ced]

Hi Veeyaarvi,

great advice, i'll take a look at that, thanks !

[IMPI-Ced]

Hi @buzzsubash ,

not sure this thread is monitored, as it is now marked as resolved, but for  point #4 i opened a case as advised and i was told support is only for "break and fix" not for initial setup or so.

Then my question is still there, if somebody has advises, that could be great

Thanks

[veeyarvi]

Hi Ced,

The support case reaches the break-fix support team and they are focused on fixing any technical issues on already existing configuration. Since the question needs to be answered from a consultantation perspective, the support case might not yeild the desired result.

Also the question should be for the network experts and not really for the Alletra MP specifically. So there may not be a perfect answer for your question related to MTU/VLAN. Whatever MTU suggested by the network experts, we can set in each port separately.

PS: My suggestion is to get the replication configuration done from HPE consultants. They will analyse, suggest and configure the replication in the best possible way according to your needs.

Regards,
Veeyaarvi

[IMPI-Ced]

Many thanks for this reply.

In fact i have no problem with network configuration as i'm very confortable with.

It is more about Alletra and what i can or cannot do with it, and the best way to achieve what i need, then no problem to configure firewall/switches/...

I guess HPE consultant will be something i have to pay for ?

I'm really surprised as my question is on a very basic setup and i guess many people have this kind of setup (2 local + 1 remote)

Have a nice day

Ced

[veeyarvi]

Hi Ced,

Yes, the consultancy is something payable and break-fix support is not the correct resources to recommend what needs to be configured in a set up. The break-fix support, as the name suggests, help with troubleshooting if an issue happens in a known working setup - not in the initial configuration.

Coming back to your question "we will have a synced replication between two Alletra and an asynced replication on a remote site. As a consequence we where obliged to set MTU to 1280 in order to be OK into the site-to-site VPN, but then MTU will be also set to 1280 for local replication, not really good. I guess i could use only ports 3 for local replication using MTU 9000 and ports 4 for remote replication using MTU 1280, but then i'll "only" have 10 Gbp between Alletra. Do i misunderstood something ? Any advice would be appreciated. "

Could you exactly tell me what is looking from Alletra MP side in this? Since you have a limitation in MTU in network for one replication (remote),  you are planning to use only one port (10Gbps) for this (if I understood correctly). It will be greateful what exactly looking from Alletra MP side in this.

Regards,
Vivek

[IMPI-Ced]

Hi Vivek,

thanks for clarification. In fact this has to deal with Alletra for best pratices and how should it be set up.

I have two replication : one sync with MTU 9000 and one async with MTU 1280.

Two solutions for me :

   - using the lowest one (1280) on ports 3 & 4, and using all these links for replication

   - dedicate port 3 to MTU 9000 and port 4 to MTU 1280, only one link per replication

None seem perfect, but for me the first one is better

But, as this seems for me a really usual setup, i guess there are others solutions : add another network card (but should be expensive), managing two subnet (vlan?) per port with different MTU, ...

For me this is Alletra related, no ?

About configuring switchs after, that my work, no worry, my concern is how should i configure Alletra.

Or there is something i misunderstood

Ced

[veeyarvi]

Hi Ced,

While refering the support matrix, I could see you can have a maximum of two links per node for remote copy. So dedicating 3 ports per node is not a supported configuration.

Regards,
Veeyaarvi

[IMPI-Ced]

Hi veeyarvi ,

there should be a misunderstood

I did not mean 3 ports, but ports 3.

On MP port 1&2 are for iSCSI, 3&4 for replication

Then what i mean was 2 choices :

   - use each port 3 for local replic using MTU 9000 and each port 4 for remote replication using MTU 1280

or

   - use port 3&4 for replication remote and local with MTU 1280... a "global" replication network

and

  - surely other solutions i never though about and that is why i opened this thread

thanks !

[Cali]

In addition to @buzzsubash,

6) I prefer "HP Pro Mini 260" or DL20 as Quorum, but also have Collegs using Rasberry.

7) With the latest Update to 10.4 the Fan and Power going down about 15-25%, but still very loud.

Cali

[IMPI-Ced]

Hi Cali,

thanks for that.

Going on a "small form factor PC" was also an option for us, because of Rasberry reliability which would be not as good as de PC.

As per your advice i'll put that solution on top of the list

We updated to 10.4 (not so easy!)  and yes they are a (little bit) less loud

Thanks !

[IMPI-Ced]

Just to clarify an error into this thread, it was given by a senior member and i can verify it when using the Alletra MP :

About Node (Controller), yes both are Active in 3PAR/Primera/Alletra MP, this is different from Nimble & Alletra 6000 and some others.

Ced