SSH access
SSH is the standard way to log in to institute servers – secure, scriptable and cross-platform.
$ ssh HU-Account@ssh.mathematik.hu-berlin.deFor everyone working with their HU account – this is the standard case.
$ ssh alter-mathe-account@math@ssh.mathematik.hu-berlin.de
The @math suffix selects the legacy maths authentication. Only needed if your account was not created at CMS.
@math.hu-berlin.de email address will also be available for HU accounts – at the moment it only works for holders of legacy maths accounts.eduroam, LAN) SSH is reachable directly.
By operating system
SSH is built in on all three platforms today – no extra client needed.
Linux
Open a terminal and connect:
$ ssh yourusername@ssh.mathematik.hu-berlin.demacOS
Open Terminal via Spotlight: ⌘ Space, type „Terminal“.
$ ssh yourusername@ssh.mathematik.hu-berlin.deSSH keys instead of password
More secure than password login and avoids repeated prompts – set up once, then never again.
-
Generate a key pair (local, one-time)
$ ssh-keygen -t ed25519 -C "HU Berlin"Accept the default path; setting a passphrase is recommended.
-
Upload the public key to the server
$ ssh-copy-id yourusername@ssh.mathematik.hu-berlin.deLog in with the password once – from then on the key is enough.
-
Log in without a password
$ ssh yourusername@ssh.mathematik.hu-berlin.de
SSH-Konfigurationsdatei (~/.ssh/config)
Avoids retyping long hostnames over and over.
Create or extend ~/.ssh/config:
Host mathlogin
HostName ssh.mathematik.hu-berlin.de
User yourusername
Host beta
HostName beta
User yourusername
ProxyJump mathloginAfter this:
$ ssh mathlogin # Login-Server
$ ssh beta # direkt auf den RechenserverConnecting to compute servers
Five dedicated servers for compute-intensive tasks.
Current load
As of 16:06 · average of the last 5 min
Most free right now: zeta.
147 of 224 threads free
alphamoderately busy · 42.3 %queuerecommended
80 cores · 160 threads · 503 GiB RAM
Intel® Xeon® Platinum 8380 @ 2.30 GHz
92of 160 threads free
ssh -J yourusername@ssh.mathematik.hu-berlin.de yourusername@alphabetamoderately busy · 34.2 %queuerecommended
52 cores · 104 threads · 1,258 GiB RAM
Intel® Xeon® Platinum 8270 @ 2.70 GHz
68of 104 threads free
ssh -J yourusername@ssh.mathematik.hu-berlin.de yourusername@betaetabusy · 52.2 %queuerecommended
112 cores · 224 threads · 3,022 GiB RAM
Intel® Xeon® Platinum 8280L @ 2.70 GHz
107of 224 threads free
ssh -J yourusername@ssh.mathematik.hu-berlin.de yourusername@etazetamoderately busy · 34.5 %queuerecommended
112 cores · 224 threads · 3,022 GiB RAM
Intel® Xeon® Platinum 8280L @ 2.70 GHz
147of 224 threads free
ssh -J yourusername@ssh.mathematik.hu-berlin.de yourusername@zetathetafree · 4.1 % busyqueuerecommended
16 cores · 32 threads · 1,007 GiB RAM
Intel® Xeon® Gold 5222 @ 3.80 GHz
31of 32 threads free
ssh -J yourusername@ssh.mathematik.hu-berlin.de yourusername@theta
Verify SSH keys
Compare the fingerprint ssh shows on first connect in full with this value. If it differs: abort, tell IT support.
Check all five at once (bash or zsh):
for s in alpha beta eta zeta theta; do ssh-keygen -lf <(ssh-keyscan -t ed25519 $s.mathematik.hu-berlin.de); done- alphaED25519
SHA256:jhwwATJd42kphvdIxz5my1zp4eNiHxk1lcB/XlMDyH4RSA-3072SHA256:RCHiYkn91ziNC71WG2qMNGUQFAuehnELpWLtBHydnKM - betaED25519
SHA256:iLx7+HbZ2QmJlQqRWeSHFT+r5rVaRgZaigclHDRM1aYRSA-3072SHA256:ky1TluRHUmWpEdojzVp1f0h0Meot/mN4NY8SVMbIbRs - etaED25519
SHA256:h3T/FkjIlazlZwjODDJz15CSw6Sxy3Gtp7tkhRyDMqkRSA-3072SHA256:t0ur7w50sZs6Fviqq0NbTfw2SO2CgZduKdSBUSNfCLg - zetaED25519
SHA256:ZDtzs3fz6rZO+ZumfCGbhnZRv3QWoICH13sQdFeTGVkRSA-3072SHA256:ZxUiMifkLpH9jfGwCVhefSpFTPyPHZqQacUuYdxRlDo - thetaED25519
SHA256:4g4s3CBecaVLMzePmHb3SZO+vzeoKnd3RI1kqi83NesRSA-3072SHA256:13901Gxff70IEEiJQu+lznspfsV+BafK9wXBlZHBbp0
Direct connection via the login server (jump host, one step):
$ ssh -J ssh.mathematik.hu-berlin.de yourusername@betaOr in two steps:
$ ssh yourusername@ssh.mathematik.hu-berlin.de
$ ssh betaKeeping sessions alive (tmux / screen)
Terminal multiplexers prevent running processes from being killed when the SSH connection drops (network issues, closed laptop, etc.).
| Action | tmux | screen |
|---|---|---|
| New session | tmux new -s name |
screen -S name |
| Detach | Ctrl+b, then d | Ctrl+a, then d |
| Reattach | tmux attach -t name |
screen -d -R name |
| List sessions | tmux ls |
screen -ls |
Transferring files
Four tools – pick by scope and comfort.
rsync
Recommended for directories: transfers only changes, with progress.
$ rsync -avz local/ yourusername@ssh.mathematik.hu-berlin.de:target/
$ rsync -avz yourusername@ssh.mathematik.hu-berlin.de:source/ local/scp
Simple for individual files.
$ scp file yourusername@ssh.mathematik.hu-berlin.de:target/
$ scp yourusername@ssh.mathematik.hu-berlin.de:source.pdf .sshfs
Mount your home directory locally – like a USB stick.
$ sshfs yourusername@ssh.mathematik.hu-berlin.de: ~/uni_home
$ fusermount -u ~/uni_homeGraphical tools
Drag & drop, no command line.
- Dolphin / Nautilus:
sftp://yourusername@ssh.mathematik.hu-berlin.de/ - WinSCP: winscp.net (SFTP)
- Cyberduck: free for macOS / Windows