This PR fixes moves resources stuck in transition state during async job cleanup
Problem:
During maintenance of the management server, other servers in the cluster or the same server after a restart initiate async job cleanup. However, this process leaves resources in a transitional state. The only recovery option currently available is to make direct database changes.
Solution:
This PR introduces a resolution by changing Volume, Virtual Machine, and Network resources from their transitional states. This adjustment enables the reattempt of failed operations without the need for manual database modifications.
Extending the current functionality of KVM Host HA for the StorPool storage plugin and the option for easy integration for the rest of the storage plugins to support Host HA
This extension works like the current NFS storage implementation. It allows it to be used simultaneously with NFS and StorPool storage or only with StorPool primary storage.
If it is used with different primary storages like NFS and StorPool, and one of the health checks fails for storage, there is an option to report the failure to the management with the global config kvm.ha.fence.on.storage.heartbeat.failure. By default this option is disabled when enabled the Host HA service will continue with the checks on the host and eventually will fence the host
This PR adds new functionality to copy snapshots across zones and take snapshots for multiple zones.
Copy functionality is similar to template copy. The source zone acts as the web server from where the destination zone(s) can download the snapshot files. For this purpose, a new API - `copySnapshot` has been added. The response for copySnapshot will be returning zone and download details from the first destination zone of the request. This behaviour is similar to the `copyTemplate` API.
In a similar manner, multiple zones can be selected while taking the snapshots or creating snapshot policies. For this snapshot will be taken in the base zone(in which volume is present) and then copied to the additional zones. A new parameter - `zoneids` has been added to `createSnapshot` and `createSnapshotPolicy` APIs.
As snapshots can be present on multiple zones (secondary stores), a new parameter `zoneid` has been added to delete the snapshot copy on a specific zone.
`listSnapshots` API has been updated to allow listing snapshot entries for different zones/datastores. New parameters - `showUnique`, `locationType` have been added.
Events generated during snapshot operations will now be linked to the snapshot itself rather than the volume of the snapshot.
`listSnapshotPolicies` and `createSnapshotPolicy` APIs will return zone details of the zones in which backup will be scheduled for the policy.
----
New API added
`copySnapshot`
Request and response params updated for APIs
```
- listSnapshots
- deleteSnapshot
- createTemplate
- listZones
- listSnapshotPolicies
- createSnapshotPolicy
```
UI updated for
- Snapshot detail view
- Create snapshot form
- Create snapshot policy form
- Create volume (from snapshot) form
- Create template (from snapshot) form
Doc PR: https://github.com/apache/cloudstack-documentation/pull/344
PR: https://github.com/apache/cloudstack/pull/7873
* Allow configkey to set 'cloud-name' cloud-init metadata
* Update engine/api/src/main/java/com/cloud/vm/VirtualMachineManager.java
Co-authored-by: Daniel Augusto Veronezi Salvador <38945620+GutoVeronezi@users.noreply.github.com>
* Update server/src/main/java/com/cloud/network/NetworkModelImpl.java
Co-authored-by: Daniel Augusto Veronezi Salvador <38945620+GutoVeronezi@users.noreply.github.com>
* Update server/src/main/java/com/cloud/network/router/CommandSetupHelper.java
Co-authored-by: Daniel Augusto Veronezi Salvador <38945620+GutoVeronezi@users.noreply.github.com>
* Revert "Update server/src/main/java/com/cloud/network/router/CommandSetupHelper.java"
This reverts commit 8abc3e38c4f973227e77253a8bcf3c94827d187f.
* Revert "Update server/src/main/java/com/cloud/network/NetworkModelImpl.java"
This reverts commit 7f239be919112913d764b141e943acca4473f755.
* Rework/Fix review code suggestions
---------
Co-authored-by: Marcus Sorensen <mls@apple.com>
Co-authored-by: Daniel Augusto Veronezi Salvador <38945620+GutoVeronezi@users.noreply.github.com>
This PR introduces a feature designed to allow CloudStack to manage a generic volume encryption setting. The encryption is handled transparently to the guest OS, and is intended to handle VM guest data encryption at rest and possibly over the wire, though the actual encryption implementation is up to the primary storage driver.
In some cases cloud customers may still prefer to maintain their own guest-level volume encryption, if they don't trust the cloud provider. However, for private cloud cases this greatly simplifies the guest OS experience in terms of running volume encryption for guests without the user having to manage keys, deal with key servers and guest booting being dependent on network connectivity to them (i.e. Tang), etc, especially in cases where users are attaching/detaching data disks and moving them between VMs occasionally.
The feature can be thought of as having two parts - the API/control plane (which includes scheduling aspects), and the storage driver implementation.
This initial PR adds the encryption setting to disk offerings and service offerings (for root volume), and implements encryption support for KVM SharedMountPoint, NFS, Local, and ScaleIO storage pools.
NOTE: While not required, operations can be significantly sped up by ensuring that hosts have the `rng-tools` package and service installed and running on the management server and hypervisors. For EL hosts the service is `rngd` and for Debian it is `rng-tools`. In particular, the use of SecureRandom for generating volume passphrases can be slow if there isn't a good source of entropy. This could affect testing and build environments, and otherwise would only affect users who actually use the encryption feature. If you find tests or volume creates blocking on encryption, check this first.
### Management Server
##### API
* createDiskOffering now has an 'encrypt' Boolean
* createServiceOffering now has an 'encryptroot' Boolean. The 'root' suffix is added here in case there is ever any other need to encrypt something related to the guest configuration, like the RAM of a VM. This has been refactored to deal with the new separation of service offering from disk offering internally.
* listDiskOfferings shows encryption support on each offering, and has an encrypt boolean to choose to list only offerings that do or do not support encryption
* listServiceOfferings shows encryption support on each offering, and has an encrypt boolean to choose to list only offerings that do or do not support encryption
* listHosts now shows encryption support of each hypervisor host via `encryptionsupported`
* Volumes themselves don't show encryption on/off, rather the offering should be referenced. This follows the same pattern as other disk offering based settings such as the IOPS of the volume.
##### Volume functions
A decent effort has been made to ensure that the most common volume functions have either been cleanly supported or blocked. However, for the first release it is advised to mark this feature as *experimental*, as the code base is complex and there are certainly edge cases to be found.
Many of these features could eventually be supported over time, such as creating templates from encrypted volumes, but the effort and size of the change is already overwhelming.
Supported functions:
* Data Volume create
* VM root volume create
* VM root volume reinstall
* Offline volume snapshot/restore
* Migration of VM with storage (e.g. local storage VM migration)
* Resize volume
* Detach/attach volume
Blocked functions:
* Online volume snapshot
* VM snapshot w/memory
* Scheduled snapshots (would fail when VM is running)
* Disk offering migration to offerings that don't have matching encryption
* Creating template from encrypted volume
* Creating volume from encrypted volume
* Volume extraction (would we decrypt it first, or expose the key? Probably the former).
##### Primary Storage Support
For storage developers, adding encryption support involves:
1. Updating the `StoragePoolType` for your primary storage to advertise encryption support. This is used during allocation of storage to match storage types that support encryption to storage that supports it.
2. Implementing encryption feature when your `PrimaryDataStoreDriver` is called to perform volume lifecycle functions on volumes that are requesting encryption. You are free to do what your storage supports - this could be as simple as calling a storage API with the right flag when creating a volume. Or (as is the case with the KVM storage types), as complex as managing volume details directly at the hypervisor host. The data objects passed to the storage driver will contain volume passphrases, if encryption is requested.
##### Scheduling
For the KVM implementations specified above, we are dependent on the KVM hosts having support for volume encryption tools. As such, the hosts `StartupRoutingCommand` has been modified to advertise whether the host supports encryption. This is done via a probe during agent startup to look for functioning `cryptsetup` and support in `qemu-img`. This is also visible via the listHosts API and the host details in the UI. This was patterned after other features that require hypervisor support such as UEFI.
The `EndPointSelector` interface and `DefaultEndpointSelector` have had new methods added, which allow the caller to ask for endpoints that support encryption. This can be used by storage drivers to find the proper hosts to send storage commands that involve encryption. Not all volume activities will require a host to support encryption (for example a snapshot backup is a simple file copy), and this is the reason why the interface has been modified to allow for the storage driver to decide, rather than just passing the data objects to the EndpointSelector and letting the implementation decide.
VM scheduling has also been modified. When a VM start is requested, if any volume that requires encryption is attached, it will filter out hosts that don't support encryption.
##### DB Changes
A volume whose disk offering enables encryption will get a passphrase generated for it before its first use. This is stored in the new 'passphrase' table, and is encrypted using the CloudStack installation's standard configured DB encryption. A field has been added to the volumes table, referencing this passphrase, and a foreign key added to ensure passphrases that are referenced can't be removed from the database. The volumes table now also contains an encryption format field, which is set by the implementer of the encryption and used as it sees fit.
#### KVM Agent
For the KVM storage pool types supported, the encryption has been implemented at Qemu itself, using the built-in LUKS storage support. This means that the storage remains encrypted all the way to the VM process, and decrypted before the block device is visible to the guest. This may not be necessary in order to implement encryption for /your/ storage pool type, maybe you have a kernel driver that decrypts before the block device on the system, or something like that. However, it seemed like the simplest, common place to terminate the encryption, and provides the lowest surface area for decrypted guest data.
For qcow2 based storage, `qemu-img` is used to set up a qcow2 file with LUKS encryption. For block based (currently just ScaleIO storage), the `cryptsetup` utility is used to format the block device as LUKS for data disks, but `qemu-img` and its LUKS support is used for template copy.
Any volume that requires encryption will contain a passphrase ID as a byte array when handed down to the KVM agent. Care has been taken to ensure this doesn't get logged, and it is cleared after use in attempt to avoid exposing it before garbage collection occurs. On the agent side, this passphrase is used in two ways:
1. In cases where the volume experiences some libvirt interaction it is loaded into libvirt as an ephemeral, private secret and then referenced by secret UUID in any libvirt XML. This applies to things like VM startup, migration preparation, etc.
2. In cases where `qemu-img` needs to use this passphrase for volume operations, it is written to a `KeyFile` on the cloudstack agent's configured tmpfs and passed along. The `KeyFile` is a `Closeable` and when it is closed, it is deleted. This allows us to try-with-resources any volume operations and get the KeyFile removed regardless.
In order to support the advanced syntax required to handle encryption and passphrases with `qemu-img`, the `QemuImg` utility has been modified to support the new `--object` and `--image-opts` flags. These are modeled as `QemuObject` and `QemuImageOptions`. These `qemu-img` flags have been designed to supersede some of the existing, older flags being used today (such as choosing file formats and paths), and an effort could be made to switch over to these wholesale. However, for now we have instead opted to keep existing functions and do some wrapping to ensure backward compatibility, so callers of `QemuImg` can choose to use either way.
It should be noted that there are also a few different Enums that represent the encryption format for various purposes. While these are analogous in principle, they represent different things and should not be confused. For example, the supported encryption format strings for the `cryptsetup` utility has `LuksType.LUKS` while `QemuImg` has a `QemuImg.PhysicalDiskFormat.LUKS`.
Some additional effort could potentially be made to support advanced encryption configurations, such as choosing between LUKS1 and LUKS2 or changing cipher details. These may require changes all the way up through the control plane. However, in practice Libvirt and Qemu currently only support LUKS1 today. Additionally, the cipher details aren't required in order to use an encrypted volume, as they're stored in the LUKS header on the volume there is no need to store these elsewhere. As such, we need only set the one encryption format upon volume creation, which is persisted in the volumes table and then available later as needed. In the future when LUKS2 is standard and fully supported, we could move to it as the default and old volumes will still reference LUKS1 and have the headers on-disk to ensure they remain usable. We could also possibly support an automatic upgrade of the headers down the road, or a volume migration mechanism.
Every version of cryptsetup and qemu-img tested on variants of EL7 and Ubuntu that support encryption use the XTS-AES 256 cipher, which is the leading industry standard and widely used cipher today (e.g. BitLocker and FileVault).
Signed-off-by: Marcus Sorensen <mls@apple.com>
Co-authored-by: Marcus Sorensen <mls@apple.com>
This PR allows the cloud admin to set either a global or domain-specific value "metadata.allow.expose.domain", and when set this allows the VM to see the name and ID of the immediate domain that contains the VM in instance metadata. This can be useful or a variety of things such as bootstrapping VM configuration and access according to domain.
This PR also deletes the CloudZonesNetworkElement because it isn't referred to anywhere, and there was initially some confusion as to whether this code needed to be updated when extending metadata. If it needs to be kept we can remove that delete from the PR.
Signed-off-by: Marcus Sorensen <mls@apple.com>
Co-authored-by: Marcus Sorensen <mls@apple.com>
Co-authored-by: dahn <daan.hoogland@gmail.com>
Co-authored-by: Daniel Augusto Veronezi Salvador <38945620+GutoVeronezi@users.noreply.github.com>
Adds option to provide custom DNS servers for isolated network, shared network and VPC tier.
New API parameters added in createNetwork API along with the corresponding response parameters.
Doc PR: apache/cloudstack-documentation#276
* Support for live patching systemVMs and deprecating systemVM.iso. Includes:
- fix systemVM template version
- Include agent.zip, cloud-scripts.tgz to the commons package
- Support for live-patching systemVMs - CPVM, SSVM, Routers
- Fix Unit test
- Remove systemvm.iso dependency
* The following commit:
- refactors logic added to support SystemVM deployment on KVM
- Adds support to copy specific files (required for patching) to the hosts on Xenserver
- Modifies vmops method - createFileInDomr to take cleanup param
- Adds configuratble sleep param to CitrixResourceBase::connect() used to verify if telnet to specifc port is possible (if sleep is 0, then default to _sleep = 10000ms)
- Adds Command/Answer for patch systemVMs on XenServer/Xcp
* - Support to patch SystemVMs - VMWare
- Remove attaching systemvm.iso to systemVMs
- Modify / Refactor VMware start command to copy patch related files to the systemvms
- cleanup
* Commit comprises of:
- remove docker from systemvm template - use containerd as container runtime
- update create-k8s-binaries script to use ctr for all docker operations
- Update userdata sent to the k8s nodes
- update cksnode script, run during patching of the cks/k8s nodes
* Add ssh to k8s nodes details in the Access tab on the UI
* test
* Refactor ca/cert patching logic
* Commit comprises of the following changes:
- Use restart network/VPC API to patch routers
- use livePatch API support patching of only cpvm/ssvm
- add timeout to the keystore setup/import script
* remove all references of systemvm.iso
* Fix keystore-cert-import invocation + refactor cert timeout in CP/SS VMs
* fix script timeout
* Refactor cert patching for systemVMs + update keystore-cert-import script + patch-sysvms script + remove patchSysvmCommand from networkelementcommand
* remove commented code + change core user to cloud for cks nodes
* Update ownership of ssh directory
* NEED TO DISCUSS - add on the fly template conversion as an ExecStartPre action (systemd)
* Add UI changes + move changes from patch file to runcmd
* test: validate performance for template modification during seeding
* create vms folder in cloudstack-commons directory - debian rules
* remove logic for on the fly template convert + update k8s test
* fix syntax issue - causing issue with shared network tests
* Code cleanup
* refactor patching logic - certs
* move logic of fixing rootdiskcontroller from upgrade to kubernetes service
* add livepatch option to restart network & vpc
* smooth upgrade of cks clusters
* Support for live patching systemVMs and deprecating systemVM.iso. Includes:
- fix systemVM template version
- Include agent.zip, cloud-scripts.tgz to the commons package
- Support for live-patching systemVMs - CPVM, SSVM, Routers
- Fix Unit test
- Remove systemvm.iso dependency
* The following commit:
- refactors logic added to support SystemVM deployment on KVM
- Adds support to copy specific files (required for patching) to the hosts on Xenserver
- Modifies vmops method - createFileInDomr to take cleanup param
- Adds configuratble sleep param to CitrixResourceBase::connect() used to verify if telnet to specifc port is possible (if sleep is 0, then default to _sleep = 10000ms)
- Adds Command/Answer for patch systemVMs on XenServer/Xcp
* - Support to patch SystemVMs - VMWare
- Remove attaching systemvm.iso to systemVMs
- Modify / Refactor VMware start command to copy patch related files to the systemvms
- cleanup
* Commit comprises of:
- remove docker from systemvm template - use containerd as container runtime
- update create-k8s-binaries script to use ctr for all docker operations
- Update userdata sent to the k8s nodes
- update cksnode script, run during patching of the cks/k8s nodes
* Add ssh to k8s nodes details in the Access tab on the UI
* test
* Refactor ca/cert patching logic
* Commit comprises of the following changes:
- Use restart network/VPC API to patch routers
- use livePatch API support patching of only cpvm/ssvm
- add timeout to the keystore setup/import script
* remove all references of systemvm.iso
* Fix keystore-cert-import invocation + refactor cert timeout in CP/SS VMs
* fix script timeout
* Refactor cert patching for systemVMs + update keystore-cert-import script + patch-sysvms script + remove patchSysvmCommand from networkelementcommand
* remove commented code + change core user to cloud for cks nodes
* Update ownership of ssh directory
* NEED TO DISCUSS - add on the fly template conversion as an ExecStartPre action (systemd)
* Add UI changes + move changes from patch file to runcmd
* test: validate performance for template modification during seeding
* create vms folder in cloudstack-commons directory - debian rules
* remove logic for on the fly template convert + update k8s test
* fix syntax issue - causing issue with shared network tests
* Code cleanup
* add cgroup config for containerd
* add systemd config for kubelet
* add additional info during image registry config
* address comments
* add temp links of download.cloudstack.org
* address part of the comments
* address comments
* update containerd config - as version has upgraded to 1.5 from 1.4.12 in 4.17.0
* address comments - simplify
* fix vue3 related icon changes
* allow network commands when router template version is lower but is patched
* add internal LB to the list of routers to be patched on network restart with live patch
* add unit tests for API param validations and new helper utilities - file scp & checksum validations
* perform patching only for non-user i.e., system VMs
* add test to validate params
* remove unused import
* add column to domain_router to display software version and support networkrestart with livePatch from router view
* Requires upgrade column to consider package (cloud-scripts) checksum to identify if true/false
* use router software version instead of checksum
* show N/A if no software version reported i.e., in upgraded envs
* fix deb failure
* update pom to official links of systemVM template
* Enhancement: create Shared networks and VPC private gateways by users
* UI bug fix: pass correct domainid in CreateSharedNetworkForm
* Update #5730: fix test failure with test_guest_vlan_range.py
* Update #5730: fix test failure with test_persistent_network.py
* Update #5730: Add since to new API commands and API parameters
* Update #5730: Get first physical network for VPC private gateway if other ways do not work
* Update #5730: code optimization (return !offering.isSpecifyVlan())
* Update #5730: fix hard-coded network offering id in test_pvlan.py
* Update #5730: skip access check on the network owner if the owner is ROOT/system
* Update #5730: overlap check on cidr/startip/endip
* Update #5730: add methods to get accountid/domainid of shared networks
* Update #5730: improve integration tests
* Update #5730: update as per GutoVeronezi's comments
* Network Sharing: give network access permission to other accounts within a domain
* network: update ip in lb/pf/dnat tables when update vm nic ip
* Update #5757: create 3 separated methods for DNAT/LB/PF update
* travis: install python3-setuptools
* Network Sharing: update integration test
* Update #5769: Remove NetworkPermission.Ops
* Update #5769: Update as per Daan's comments
* Update #5769: Update as per Suresh's comments
* Update #5769: fix UI bug that accounts/projects are not listed
* Update #5769: fix domain admin can deploy vm on L2 network of other users
* Update #5769: Remove method listPermittedNetworkIdsByDomains in NetworkPermissionDao
* Update #5769: Skip network operation permissions check for root admin
* UI: fix create Isolated/L2 network form
* Update #5730: fix create Shared network form
* Update #5769: fix domain admin can deploy vm on L2 network of other users
* test: fix test_storage_policy.py
* Update #5769: fix remove_nic in test_network_permissions.py
* Update #5769: extract some codes to a method
* Update #5769: fix add/remove nic by domain admin
* Update #5769: allow domain admin to enable/disable static nat and create port forwarding rules
* Update #5769: update integration test
* Update #5769: fix unit test AssignLoadBalancerTest.java
* Update #5769: allow normal users to share network permission to other users on UI
* Update #5769: fix small UI bug with label
* Update #5769: Support L2 network as associated network
* test: sleep 30s after restarting mgt server in test_kubernetes_supported_versions.py to fix test failures with test_secondary_storage.py
* Update #5784: revert part of changes in #2420
* Update #5757: invert if condition to reduce code indentation
* Update #5769: fix regular user cannot create L2 network
* Update #5769: Add associated nework id and name in private gateway response
* Update #5769: list networks by networkfilter=Account on UI
* Update #5769: fix ui issue when list private gateways or create shared network if no isolated networks
* Update #5769: fix vue ui warnings
* Update #5679: add BaseResponseWithAssociatedNetwork and extract method setResponseAssociatedNetworkInformation
* Update #5679: extract some methods in VpcManagerImpl.java
* Update #5679: Update smoke tests as per Daan's comments
* Update #5769: fix vpc with private gateways cannot be removed when remove an acount
* Update #5769: fix unit test failures after merging latest main
* Update #5769: fix schema-41610to41700.sql
* Update #5769: fix Request failed due to empty network offering list on UI
* Update #5769: Throw exception when account is not found by name
* Update #5769: display a warning message if network offering list is empty
* Update #5769: fix an UI bug caused by previous commit b286cb76774e301d15cf2b3b6ea316eaa306018f
* Update #5769: fix UI bugs due to vue3 merge
* Update #5769: fix issue due to account type refactoring
* Update #5769: fix ui bugs due to vue3
* Update #5769: fix issue due to vue3 upgrade
* Update #5769: fix issue due to vue3 upgrade part 2
* Update #5769: fix issue due to vue3 upgrade part 3
* Update #5769: highlight default scope when create shared network on UI
* Update #5769: fix domain list is not loaded on UI
* Update #5769: fix restart/delete shared network by normal users
* Update #5769: fix restart domain-scope shared network by domain admin
* Update #5769: fix 3 UI bugs (1) double networks in list; (2) icon of first items in list; (3) account/project autoselect
* Update #5769: fix 2 ui bugs; (1) selected project is not changed when change domain; (2) no network should be selected by default
* Update #5769: fix update shared networks by domain admin/regular user
* Update #5769: fix Flicking warning message about the empty network offerings
* Update #5769: display associated network name in shared network info card
* Update #5769: fix create private gateway form
* Update #5769: fix network lists in project view
* Update #5769: fix duplicated networks in network dropdown
* Update #5769: fix failed to create shared network if associated L2 network is Setup
* Update #5769: check AccessType.OperateEntry on network in its implementation
* Revert "Update #5769: check AccessType.OperateEntry on network in its implementation"
This reverts commit c42c489e5bb26e2c780ac1be79bc8ca299a23f6e.
* Update #5769: fix keyword search in list guest vlans
* StorPool storage plugin
Adds volume storage plugin for StorPool SDS
* Added support for alternative endpoint
Added option to switch to alternative endpoint for SP primary storage
* renamed all classes from Storpool to StorPool
* Address review
* removed unnecessary else
* Removed check about the storage provider
We don't need this check, we'll get if the snapshot is on StorPool be
its name from path
* Check that current plugin supports all functionality before upgrade CS
* Smoke tests for StorPool plug-in
* Fixed conflicts
* Fixed conflicts and added missed Apache license header
* Removed whitespaces in smoke tests
* Added StorPool plugin jar for Debian
the StorPool jar will be included into cloudstack-agent package for
Debian/Ubuntu
* Refactor create volume snapshot with running VM
* Refactor create volume snapshot with stopped VM
* Refactor create volume from snapshot
* Refactor create template from snapshot
* Refactor volume migration (migrateVolume/ migrateVirtualMachineWithVolume)
* Refactor snapshot deletion
* Refactor snapshot revertion
* Adjusts and fix cherry-pick conflicts
* Remove diffuse tests
* Add validation to add flag '--delete' on command 'virsh blockcommand' only if libvirt version is equal or higher 6.0.0
* Expunge temporary snapshot only if template creation is from snapshot
* Extract strings to constant
* Remove unused imports
* Fix error on revert backed up snapshot
* Turn method's return to void as it is not used
* Rename method in SnapshotHelper
* Fix folder creation when using SharedMountPoint pool
* Remove static import
* Remove unnused method
* Cover take snapshot in centos 7
* Handle right snapshot flag according to qemu version
Co-authored-by: GutoVeronezi <daniel@scclouds.com.br>
* Persistent Network feature & Marvin component tests
* Cleaned up comments and imports
* fixed small error
* add support to add setup persistent networks' resources when a disabled host is enabled
* small fix
* use wildcard instead of hard-coding the bridge name
* allow clean up of resources when removing a host in maintenance mode
* skip test for simulator hypervisor
Co-authored-by: shatoboar <sang-woo.bae@campus.tu-berlin.de>
