Calypso (retired)

Retired 2026-08-28

Calypso was the students' SLURM/Docker sandbox on Ubuntu, calypso0–calypso7 plus the R740 master. The nodes were wiped and reinstalled as carnaval Proxmox nodes — calypsoN became carnavalN with the same address (rebuild entry). What was rescued from the local disks sits in rumba:/hdd/backup/calypso-preinstall/<node>/ (home/, etc/, calypso0/slurm_acct_db.sql.gz, 99 GB, no other copy). The student homes on the NAS were untouched and still mount in the lab VMs. calypsomaster still exists and awaits its conversion to mgmt-01. This page is the record of what the cluster was; nothing below runs any more.

The students sandbox cluster, hosted onsite. This page covers the machines and storage; the network layout is on ISC³ network and the software configuration (accounts, container runtimes, SLURM, registry) on Calypso software stack.

At a glance

Role	Students sandbox cluster
Machines	1× Dell R740 (master) + 8× Dell R630 workers, of 18 R630 racked
Student nodes	calypso0 – calypso7, of which calypso5 – calypso7 are powered off
RAM	128 GB per worker node
GPUs	NVIDIA A2, one per node
Storage	NFS share from the FS2500 NAS mounted on every node
Network	Isolated network behind the NetBird VPN
Access	VPN, then SSH

Hardware

• 1× Dell R740 (calypsomaster), tag 8MYS2T2, BIOS 2.21.2 — not an R740XD, as this page said until 2026-08-13. 2× Xeon Gold 6154 @ 3.0 GHz (36 c / 72 t total); 192 GB RAM as 6× 32 GB DDR4-2666 with 18 of the 24 slots free. Backplane BP14G+, 8 × 2.5" SFF bays with 4 populated — 4× Toshiba THNSN81Q 1.92 TB SATA SSD behind a PERC H730 Adapter (PCIe slot 2), presented as a single RAID6 virtual disk calypso, 3.84 TB usable. Runs Ubuntu 24.04.3 LTS. The bay count is what rules it out as pbs-02. (Re-read from the host and the iDRAC, 2026-08-15.)
• Provenance: calypsomaster and all 18 R630 were bought at ServerShop24 in four batches, Nov 2023 – Apr 2025 — invoice-by-invoice detail in the acquisition register (2026-08-17).
• 18× Dell R630: 8 active workers (calypso0 – calypso7), 3 converted to carnaval, and 7 racked spares (see the rack layout) — the spares answer on no protocol, their iDRACs having never been put on the management LAN, so nothing about them can be checked remotely (todo)
• Each worker has 128 GB RAM and one NVIDIA A2 (16 GB) GPU:
  • CPU: 2× Intel Xeon E5-2690 v3 @ 2.6 GHz (48 threads) or 2× Intel Xeon E5-2697 v4 @ 2.3 GHz (72 threads), depending on the node — see the table below

The GPUs are usable from within containers through the NVIDIA Container Toolkit; see Calypso software stack for details.

Node specifications

Node	CPU	GPU
calypso0	2× E5-2690 v3 (48 threads)	NVIDIA A2
calypso1	2× E5-2697 v4 (72 threads)	NVIDIA A2
calypso2	2× E5-2697 v4 (72 threads)	NVIDIA A2
calypso3	2× E5-2697 v4 (72 threads)	NVIDIA A2
calypso4	2× E5-2690 v3 (48 threads)	NVIDIA A2
calypso5	—	NVIDIA A2
calypso6	—	NVIDIA A2
calypso7	—	NVIDIA A2

Node IP addresses are listed on the Calypso network page.

Specs verified directly on the nodes (July 2026); calypso5 – calypso7 were down at that time, so their CPU model is not listed and their GPU comes from the software stack documentation. The three ex-nodes calypso8 – calypso10 are specced on the carnaval page, where their CPUs and RAM were measured — and two of the three differed from what was assumed here (calypso8/9 are E5-2683 v4, calypso10 has 112 GB, not 128).

PERC batteries and PSUs

Fleet sweep of 2026-08-04 over the eleven reachable node iDRACs (192.168.90.10–.20). Two parts have been harvested from these chassis over time: the redundant PSU (all eleven now run on PS2 alone) and the PERC H730P Mini battery. Fitting the kits that are on hand is an open item.

Node	iDRAC	Host	PERC battery	Reading
calypso0	.10	on	Ok / Ready	live
calypso1	.11	on	Failed / Removed	live
calypso2	.12	on	Failed / Removed	live
calypso3	.13	off	Ok / Ready	stale
calypso4	.14	off	Unknown / Ready	stale
calypso5	.15	off	no battery object enumerated	stale
calypso6	.16	off	Unknown / Ready	stale
calypso7	.17	off	Unknown / Removed	stale
carnaval0	.18	on	Failed / Removed	live
carnaval1	.19	on	Ok / Ready	live
carnaval2	.20	on	Ok / Ready	live

Read with racadm storage get batteries -o. A powered-off node returns last-known inventory, not a live reading — racadm says so itself (STOR0102 … Check if the server has power), which is why five rows are marked stale. The seven spare R630s (.21–.27) answer on no protocol, so their BBUs are unknown: don't assume a spare is complete.

Never force Write-Back on a node with no BBU

With the battery absent the H730P runs Write-Through, which is safe. Forcing Write-Back to win back write speed is data loss on a power cut — and these nodes no longer have a redundant PSU either.

Clearing the alerts: an iDRAC GracefulRestart re-inventories the chassis and drops a genuinely absent PSU (done on .10–.13, health Critical → OK; clearing the SEL alone does not work, and the iDRAC needs 80–160 s to return). It does not clear an absent BBU — that re-asserts within a minute, being a live fact rather than a stale log entry. No software fix exists short of the controller-side batterywarning=off knob, which needs perccli on the host and may not satisfy iDRAC's own health rollup anyway.

Storage

Storage shared between all Calypso nodes comes from the rack's Synology FS2500 NAS (nas, 192.168.88.250), mainly for SLURM needs: jobs can run on any node against a common filesystem and write their results there. Hardware, volumes and NFS exports are detailed on the NAS page.

On the nodes, the filesystem is mounted from nas:/volume1/calypso_homes/homes/firstname.lastname to each student's shared directory /exports/firstname.lastname/.

In each student's home there is a symlink to it: ~/nas_home.