Re: [gpfsug-discuss] Experiences with Synchronous Replication, Stretch Clusters, and Spectrum Scale <= 4.2
On Sat, 07 Apr 2018 20:27:49 +0300, "Yaron Daniel" said: > Main items to take into account : > 1) What is the latecny you have between the 2 main sites ? > 2) What network bandwidth between the 2 sites ? > 3) What is the latency to the 3rd site from each site ? > 4) Which protocols plan to be used ? Do you have layer2 between the 2 sites > , or layer 3 ? > 5) Do you plan to use dedicated network for GPFS daemon ? The answers to most of these questions are a huge "it depends". For instance, the bandwidth needed is dictated by the amount of data being replicated. The cluster I mentioned the other day was filling most of a 10Gbit link while we were importing 5 petabytes of data from our old archive solution, but now often fits its replication needs inside a few hundred mbits/sec. Similarly, the answers to (4) and (5) will depend on what long-haul network infrastructure the customer already has or can purchase. If they have layer 2 capability between the sites, that's an option. If they've just got commodity layer-3, you're designing with layer 3 in mind. If their network has VLAN capability between the sites, or a dedicated link, that will affect the answer for (5). And so on... pgpKF0JzRO9ux.pgp Description: PGP signature ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
Re: [gpfsug-discuss] Experiences with Synchronous Replication, Stretch Clusters, and Spectrum Scale <= 4.2
HI We have few customers than have 2 Sites (Active/Active using SS replication) + 3rd site as Quorum Tie Breaker node. 1) Spectrum Scale 4.2.3.x 2) Lenovo x3650 -M4 connect via FC to SVC (Flash900 as external storage) 3) We run all tests before deliver the system to customer Production. Main items to take into account : 1) What is the latecny you have between the 2 main sites ? 2) What network bandwidth between the 2 sites ? 3) What is the latency to the 3rd site from each site ? 4) Which protocols plan to be used ? Do you have layer2 between the 2 sites , or layer 3 ? 5) Do you plan to use dedicated network for GPFS daemon ? Regards Yaron Daniel 94 Em Ha'Moshavot Rd Storage Architect Petach Tiqva, 49527 IBM Global Markets, Systems HW Sales Israel Phone: +972-3-916-5672 Fax: +972-3-916-5672 Mobile: +972-52-8395593 e-mail: y...@il.ibm.com IBM Israel From: "Howard, Stewart Jameson" To: "gpfsug-discuss@spectrumscale.org" Date: 04/06/2018 06:24 PM Subject:[gpfsug-discuss] Experiences with Synchronous Replication, Stretch Clusters, and Spectrum Scale <= 4.2 Sent by:gpfsug-discuss-boun...@spectrumscale.org Hi All, I was wondering what experiences the user group has had with stretch 4.x clusters. Specifically, we're interested in: 1) What SS version are you running? 2) What hardware are you running it on? 3) What has been your experience with testing of site-failover scenarios (e.g., full power loss at one site, interruption of inter- site link). Thanks so much for your help! Stewart ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org https://urldefense.proofpoint.com/v2/url?u=http-3A__gpfsug.org_mailman_listinfo_gpfsug-2Ddiscuss&d=DwIGaQ&c=jf_iaSHvJObTbx-siA1ZOg&r=Bn1XE9uK2a9CZQ8qKnJE3Q&m=yYIveWTR3gNyhJ9KsrodpWApBlpQ29Oi858MuE0Nzsw&s=V42UYnHtEYVK3LvH6i930tzte1qp0sWmiY6Pp1Ep3kg&e= ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
Re: [gpfsug-discuss] Experiences with Synchronous Replication, Stretch Clusters, and Spectrum Scale <= 4.2
Hi Stewart We're running a synchronous replication cluster between our DCs in London and Slough, at a distance of ~63km. The latency is in the order of 700 microseconds over dark fibre. Honestly... it's been a fine experience. We've never had a full connectivity loss mind you, but we have had to shut down one site fully whilst the other one carried on as normal. Mmrestripe afterwards of course. We are running Scale version 4.2.3 and looking at v5. Hardware is IBM v3700 storage, IBM rackmount NSD/CES nodes. The storage is connected via FC. Cheers Richard -Original Message- From: gpfsug-discuss-boun...@spectrumscale.org On Behalf Of Howard, Stewart Jameson Sent: 06 April 2018 16:15 To: gpfsug-discuss@spectrumscale.org Subject: [gpfsug-discuss] Experiences with Synchronous Replication, Stretch Clusters, and Spectrum Scale <= 4.2 Hi All, I was wondering what experiences the user group has had with stretch 4.x clusters. Specifically, we're interested in: 1) What SS version are you running? 2) What hardware are you running it on? 3) What has been your experience with testing of site-failover scenarios (e.g., full power loss at one site, interruption of inter- site link). Thanks so much for your help! Stewart ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss ___ gpfsug-discuss mailing list gpfsug-discuss at spectrumscale.org http://gpfsug.org/mailman/listinfo/gpfsug-discuss
