Words and their Meanings
We will try to avoid using ambiguous terms like 'NGAS server' in favor of more specific terms:
- NGAS Service: an instance of the the NGAS software running on an NGAS node.
- Service Number: an enumeration of the NGAS services running on an NGAS node
- Port Number: the tcp/ip port an NGAS service listens to.
- NGAS Node: a computer running one or more NGAS services.
- NGAS Cluster: one or more NGAS nodes sharing a common cluster name and relational database.
- NGAS Root directory: the base directory a service executes from.
- NGAS Volume: a storage partition NGAS uses to store files
- NGAS Copy Node: an NGAS Node that is a duplicate of another NGAS node, using subscription or rsync
NGAS Node Host Names
Server host names follow this general format and should be under 128 characters long:
$SITE-$CLUSTER-ngas-$PROFILE-$NUMBER, e.g. soc-ssa-ngas-prod-001
What the Node Host Name Components Mean
$SITE | $CLUSTER | $PROFILE | $NUMBER |
|---|---|---|---|
2 to 3 lowercase letters representing site location:
Non-NRAO Sites:
|
|
| 001 onwards |
Mapping Old Node Host Names to New Node Host Names
Old Name | New Name | Old Name | New Name |
|---|---|---|---|
| nmngas01 | soc-ssa-ngas-prod-001 | cvngas01 | cv-ssa-ngas-prod-001 |
| nmngas02 | soc-ssa-ngas-prod-002 | cvngasttest01 | cv-ssa-ngas-test-001 |
| nmngas03 | soc-ssa-ngas-prod-003 | cvngas01-mirror | uva-ssa-ngas-copy-001 |
| nmngas04 | soc-ssa-ngas-prod-004 | vegas-arc-03 | uva-ssa-ngas-prod-001 |
| nmngas01mirror | nmt-ssa-ngas-copy-001 | vegas-arc-04 | uva-ssa-ngas-prod-002 |
| nmngas02mirror | nmt-ssa-ngas-copy-002 | ngas-01 | cv-naasc-ngas-prod-001 |
| nmngas03mirror | nmt-ssa-ngas-copy-003 | ngas-02 | cv-naasc-ngas-prod-002 |
| nmngas04mirror | nmt-ssa-ngas-copy-004 | ngas-03 | cv-naasc-ngas-prod-003 |
| nmngastest01 | soc-ssa-ngas-test-001 | ||
| nmngastest02 | soc-ssa-ngas-test-002 |
Ports and Service Numbers
A given NGAS node can be configured to run more than one service, this can be described as a service number and a port number. The first service on a node will be service number 1, and it will bind to port 7777. Subsequent services increment both the service number and port number, so the second service on a node would be service number 2, port 7778, and so on.
Partition Names and Mount Points
- NGAS nodes will have one root directory per service:
- The root directory will be /NGAS$Number, so, /NGAS1 for the first service, /NGAS3 for the third and so on.
- Nodes that will only run one service can use /NGAS for the root directory, omitting the service number.
- Volumes will be named VolumeNN, where NN is a zero padded number starting at 1, so Volume01, Volume02 and so on.
- Volumes will be mounted at $ROOT_DIRECTORY/volumes/$VOLUME_NAME
- e.g. /NGAS2/volumes/Volume03, /NGAS/volumes/Volume12
Alerts, Monitoring & Logging
- We will aggregate logs in the SSA metrics server.
- We will provide service interruption alerts via Slack
- We will track the load on the NGAS servers via the metrics server
- This will be set up and configured on each host via an Ansible playbook