Failed to read from defunct connection (Jupyter notebook, python driver )

[LJRB]

I try to import data into a Neo4j VM in Azure.

This code works:

def create_article(tx):
    tx.run("CREATE (a:ARTICLE)")

session.read_transaction(create_article)

But this code doesn't work:

def create_node_article(tx, id, title, label):
    tx.run("CREATE (a:ARTICLE {id:$id, title:$title, label:$label})", id=id, title=title, label=label)

for index, row in df_article_ids.iterrows():
    session.read_transaction(create_node_article, row['id'], row['cleaned_best_title'], row['label'])

I have the error:

Transaction failed and will be retried in 1.0608892687544587s (Failed to read from defunct connection Address(host='IP', port=7687) (Address(host='IP', port=7687)))

I don't know what I have to change or check. I also tried Neo4j Desktop and I have the same error.

Neo4j version: 4.1.3

[mark_needham]

Could you include the full code sample that you're trying to get working?

[carib]

LJRB:

port data into a Neo4j VM in Azure.

This code works:

Hello,

I have the same problem with the official Python Driver and Neo4j. I've been receiving this error: "Failed to read from defunct connection IPv4Address(('HOST', 7687)) (IPv4Address(('IPADDRESS', 7687)))"

It seems like there are already open GitHub issues for this, but there are no updates yet as far as I can tell.

github.com/neo4j/neo4j-python-driver

ServiceUnavailable Defunct Connection Address - after a certain period of time

opened 10:13PM - 21 Jun 19 UTC

closed 09:05PM - 23 Jun 19 UTC

Zhenshan-Jin

The neo4j driver will give the error `neobolt.exceptions.ServiceUnavailable: Fai…led to read from defunct connection Address(host='<remote neo4j bolt>', port=7687)` if certain amount of time spent between the creation of neo4j client and creation of the session. However, if I start the session the second time, the error is gone. ``` from neo4j import GraphDatabase import time neo4j_url = "bolt://<remote_neo4j_url>:7687" user_name = "neo4j" password = "" neo4j_client = GraphDatabase.driver(neo4j_url, auth=(user_name, password)) time.sleep(300) # 5 minutes query = '''MATCH (n) RETURN n LIMIT 1''' # with error try: with neo4j_client.session() as session: query_result = session.run(query) except Exception as e: print(str(e)) # no error with neo4j_client.session() as session: query_result = session.run(query) ``` ------------------------ Environment: python 3.6 neo4j==1.7.2 neobolt==1.7.4 neotime==1.7.4 mac 10.14.4

github.com/neo4j/neo4j-python-driver

Failed to read from defunct connection Address

opened 09:13AM - 10 Dec 20 UTC

closed 04:45PM - 20 Apr 21 UTC

lingvisa

Neo4j 4.2.1 Python Bolt Driver Mac I am installing the latest version of Ne…o4j 4.2.1 and got an error message when executing a cypher through Bolt driver in Python: `Transaction failed and will be retried in 1.0107646365462932s (Failed to read from defunct connection Address(host='localhost', port=7687) (Address(host='::1', port=7687, flow_info=0, scope_id=0)))` The code is like this: ``` class KGLoader(object): def __init__(self): config = Configuration.get_configs() self.schemas = config.schemas self.neo4j_driver = config.get_driver() with self.neo4j_driver.session() as session: current_indexes = KGLoader.get_all_indexes(session) if 'NameIndex' not in current_indexes: session.write_transaction(lambda tx: tx.run(cypher)) print('\nFull text NameIndex created!') @staticmethod def get_all_indexes(session): all_indexes = set() indexes = session.read_transaction( lambda tx: tx.run("CAll db.indexes")) for index in indexes: all_indexes.add(index[1]) return all_indexes KG_LOADER = KGLoader() ``` Also, the get_driver() method in Configuration class: ``` def get_driver(self): try: return GraphDatabase.driver(self.uri, auth=(self.username, self.password), encrypted=False) except: raise ValueError("Can't connect the neo4j database. Make sure the DB is up: {} {} {}".format(self.username, self.password, self.uri)) ``` The cypher is this: `CALL db.index.fulltext.createNodeIndex('NameIndex', ['Product', 'Computer'], ['name', 'alias'])` The same code doesn't have this problem in neo4j 4.0.4. Is the Python Bolt Driver for 4.2 not working yet? There is an issue registered here: https://github.com/neo4j/neo4j-python-driver/issues/294 However, that issue is not exactly the same as mine.

Has anyone on this forum managed to solve this issue?

For me, I tend to see this error message particularly often on those days when my python code updates the Neo4j graph database with csv files around 1G or more. Based on what I read on those GitHub threads, at some point the Python driver loses the connection to Neo4j if a considerable amount of times has passed. But I still find that a bit odd because on other days the updates finish in about 6 hours so clearly the connection remains even after a couple of hours.

I'm going to try to increase the

max_connection_lifetime=200

parameter so that the connection is maintained longer but people are saying that does not solve the problem.

Thanks