Right now I get IP:PORT [generadedId] in node name.
Is there a way to label it like "Service node 1 [generadedId]"?
Unfortunately this is not possible as of perfino 4.0.
Related
I am using declarative pipeline, I have 2 labels mentioned as below
agent { label 'first-pref || second-pref' }
with this, a free node gets picked up randomly either from first-pref or second-pref label, but I need the build to pick up node from second-pref ONLY IF first-pref has no free node, in other words, the nodes from first-pref should be considered first, is there a way to do that?
I am writing my master thesis with Neo4j Database and I meet a problem. I need your help.
The picture at left is the data I saved in Neo4j, the whole picture represents how an application could be deployed in cloud. Every node represents a service.
For example, I have an Apach Module and I can "hosted_on" an Apache Server. The green line represents a possible option, because an Apache server can hosted on a Windows system or a Linux system.
So there are two possibilities for deployment, showed at right.
At right is what I want, I call it topology, it defines how an application deployment looks like.
what I want is to retrieve all possible typologies.
How I can get these possibilities topology by Cypher or Java traverse API?
Thanks very much..
I'm not sure if this is what you are getting at, but it might be helpful to consider the "What is related and how?" query:
// What is related, and how
MATCH (a)-[r]->(b)
WHERE labels(a) <> [] AND labels(b) <> []
RETURN DISTINCT head(labels(a)) AS This, type(r) as To, head(labels(b)) AS That
LIMIT 10
This will return Node labels and relationship names that are connected by at least one relationship in the graph. Is that what you mean by topology?
I'm using ne04j 2.1.2 community edition.
I have a nodes with a label called Company and I created these nodes and label by loading CSV file along with the MERGE and CREATE commands.
So in future if my label names changes,say Company to Organization, I wanted to maintain the createddate, UpdatedDate, NewLabelName, OldLabelName values somewhere.
So in order to achieve that I thought of maintaining one master node which holds the label information i.e., it should have the properties like NewLabelName, OldLabelName, CreatedDate, UpdatedDate. So the label name should come from the Master Node to other nodes. Whenever we made any changes to label ,then the corresponding UpdatedDate property value should be updated in the master node and NewLabelName should come from the master node to other nodes (nodes for which that label belongs to) .
Hope you understand the scenario here.
But how can i achieve this ? is it possible to achieve ? if yes, then how can i define the relationship between master and other nodes?
(Here my other nodes are Name of the Companies like Google, Yahoo, Samsung etc.. and those will be having some other child nodes like location)
Please suggest the solution. (I wanted to achieve these using cypher not using java)
Thanks
Although labels can be changed, you should do that rarely (e.g., to recover from a mistake). Changing a large number of labels is very expensive and should never be done as a part of normal processing.
Also, like a Java class name, a label name is not something you'd normally show to end users. So, there is really no reason to ever change them. Just try to pick reasonable label names to start with, and don't plan to change them.
in erlang otp when making a gen_server:call(), you have to send in the name of the node, to which you are making the call.
Lets say I have this usecase:
I have two nodes: 'node1' and 'node2' running. I can use those nodes to make gen_server:call() to each other.
Now lets say I added 2 more nodes: 'node3' and 'node4' and pinged each other so that all nodes can see and make gen_server:calls to each other.
How do the erlang pros handle the dynamic adding of new nodes like that so that they know the new node names to enter into the gen_server calls, or is it a requirement to know beforehand the names of all the nodes so that they are hardcoded in somewhere like the sys.config?
you can use:
erlang:nodes()
to get a "now" view of the node list
Also, you can use:
net_kernel:monitor_nodes(true) to be notified as nodes come and go (via ping / crash / etc)
To see if your module is running on that node you can either call the gen_server with some kind of ping callback
That, or you can use the rpc module to call erlang:whereis(name) on the foreign node.
I have a bad node (it doesn't exist) in the mnesia cluster data when I get:
> mnesia:system_info(db_nodes)
[bad#node, ...]
How do I remove it from the cluster?
I tried:
> mnesia:del_table_copy(scheme, bad#node).
{aborted,{not_active,"All replicas on diskfull nodes are not active yet"...
What does this mean? How can I fix it?
Update. Before remove node from schema we need to stop mnesia on it
I had a similar problem years ago. What you are trying to do is remove an offline node, which as far as I am aware was impossible in earlier versions of mnesia.
You can however connect to the cluster using a dummy node named bad#node, and started with a tweaked system.config of the original clustered node. Once its online remove from the cluster.