number of replicas per data center?
How do people normally setup multiple data center replication in terms of number of *local* replicas? So say you have two data centers, do you have 2 local replicas, for a total of 4 replicas? Or do you have 2 in one datacenter, and 1 in another? If you only have one in a local datacenter then when it fails you have to transfer all that data over the WAN. -- Founder/CEO Spinn3r.com Location: *San Francisco, CA* blog: http://burtonator.wordpress.com … or check out my Google+ profile https://plus.google.com/102718274791889610666/posts http://spinn3r.com
Re: number of replicas per data center?
Ah.. six replicas. At least its super inexpensive that way (sarcasm!) On Sun, Jan 18, 2015 at 8:14 PM, Jonathan Haddad j...@jonhaddad.com wrote: Sorry, I left out RF. Yes, I prefer 3 replicas in each datacenter, and that's pretty common. On Sun Jan 18 2015 at 8:02:12 PM Kevin Burton bur...@spinn3r.com wrote: 3 what? :-P replicas per datacenter or 3 data centers? So if you have 2 data centers you would have 6 total replicas with 3 local replicas per datacenter? On Sun, Jan 18, 2015 at 7:53 PM, Jonathan Haddad j...@jonhaddad.com wrote: Personally I wouldn't go 3 unless you have a good reason. On Sun Jan 18 2015 at 7:52:10 PM Kevin Burton bur...@spinn3r.com wrote: How do people normally setup multiple data center replication in terms of number of *local* replicas? So say you have two data centers, do you have 2 local replicas, for a total of 4 replicas? Or do you have 2 in one datacenter, and 1 in another? If you only have one in a local datacenter then when it fails you have to transfer all that data over the WAN. -- Founder/CEO Spinn3r.com Location: *San Francisco, CA* blog: http://burtonator.wordpress.com … or check out my Google+ profile https://plus.google.com/102718274791889610666/posts http://spinn3r.com -- Founder/CEO Spinn3r.com Location: *San Francisco, CA* blog: http://burtonator.wordpress.com … or check out my Google+ profile https://plus.google.com/102718274791889610666/posts http://spinn3r.com -- Founder/CEO Spinn3r.com Location: *San Francisco, CA* blog: http://burtonator.wordpress.com … or check out my Google+ profile https://plus.google.com/102718274791889610666/posts http://spinn3r.com
Re: keyspace not exists?
log does not show anything fishy, because it is just for fun cluster, we
can actually wipe our 3 nodes cluster casandra dir,
data,saved_caches,commitlog and start it all over, we encounter the same
problem.
two nodes running cassandra 2.1.2 and one running cassandra 2.1.1
I look a look at the issue given by Tyler link, and patch my cqlsh and
given more information below and thank you it works. Actually doing this
tutorial from this blog http://www.datastax.com/dev/blog/thrift-to-cql3
$ cqlsh 192.168.0.2 9042
Warning: schema version mismatch detected; check the schema versions of
your nodes in system.local and system.peers.
Connected to just4fun at 192.168.0.2:9042.
[cqlsh 5.0.1 | Cassandra 2.1.1 | CQL spec 3.2.0 | Native protocol v3]
Use HELP for help.
cqlsh DESCRIBE KEYSPACES;
system_traces jw_schema1 system
cqlsh use jw_schema1;
cqlsh:jw_schema1 desc tables;
user_profiles
cqlsh:jw_schema1 quit;
$ cassandra-cli -h 192.168.0.2 -p 9160
Connected to: just4fun on 192.168.0.2/9160
Welcome to Cassandra CLI version 2.1.1
The CLI is deprecated and will be removed in Cassandra 3.0. Consider
migrating to cqlsh.
CQL is fully backwards compatible with Thrift data; see
http://www.datastax.com/dev/blog/thrift-to-cql3
Type 'help;' or '?' for help.
Type 'quit;' or 'exit;' to quit.
[default@unknown] show keyspaces;
WARNING: CQL3 tables are intentionally omitted from 'show keyspaces' output.
See https://issues.apache.org/jira/browse/CASSANDRA-4377 for details.
Keyspace: jw_schema1:
Replication Strategy: org.apache.cassandra.locator.SimpleStrategy
Durable Writes: true
Options: [replication_factor:3]
Column Families:
ColumnFamily: user_profiles
Key Validation Class: org.apache.cassandra.db.marshal.UTF8Type
Default column value validator:
org.apache.cassandra.db.marshal.BytesType
Cells sorted by: org.apache.cassandra.db.marshal.UTF8Type
GC grace seconds: 864000
Compaction min/max thresholds: 4/32
Read repair chance: 0.0
DC Local Read repair chance: 0.1
Caching: KEYS_ONLY
Default time to live: 0
Bloom Filter FP chance: 0.01
Index interval: default
Speculative Retry: 99.0PERCENTILE
Built indexes: []
Column Metadata:
Column Name: first_name
Validation Class: org.apache.cassandra.db.marshal.UTF8Type
Column Name: year_of_birth
Validation Class: org.apache.cassandra.db.marshal.Int32Type
Column Name: last_name
Validation Class: org.apache.cassandra.db.marshal.UTF8Type
Compaction Strategy:
org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy
Compression Options:
sstable_compression: org.apache.cassandra.io.compress.LZ4Compressor
Keyspace: system:
..
..
..
Keyspace: system_traces:
Replication Strategy: org.apache.cassandra.locator.SimpleStrategy
Durable Writes: true
Options: [replication_factor:2]
Column Families:
[default@unknown] use jw_schema1;
Authenticated to keyspace: jw_schema1
[default@jw_schema1] list user_profiles;
Using default limit of 100
Using default cell limit of 100
0 Row Returned.
Elapsed time: 728 msec(s).
[default@jw_schema1]
On Sat, Jan 17, 2015 at 6:41 AM, Tyler Hobbs ty...@datastax.com wrote:
This might be https://issues.apache.org/jira/browse/CASSANDRA-8512 if
your cluster has a schema disagreement. You can apply the patch on that
ticket with patch -p1 8512-2.1.txt from the top-level cassandra
directory and see if it helps.
On Fri, Jan 16, 2015 at 11:58 AM, Julien Anguenot jul...@anguenot.org
wrote:
Hey Jason,
Your RF=3, do you have 3 nodes up and running in this DC? We have seen
this issue with 2.1.x and cqlsh where schema changes would trigger the
keyspace not found error in cqlsh if not all nodes were up and
running when altering KS schema in a DC with NetworkTopologyStrategy
and RF=3. For us, bringing all the nodes up to meet RF would then fix
the problem.
As well, you might want to restart the node and see if the keyspace
not found still occurs: same here, since 2.1.x we've had cases where
a restart was required for cqlsh and / or drivers to see the schema
changes.
J.
On Fri, Jan 16, 2015 at 3:56 AM, Jason Wee peich...@gmail.com wrote:
$ cqlsh 192.168.0.2 9042
Connected to just4fun at 192.168.0.2:9042.
[cqlsh 5.0.1 | Cassandra 2.1.1 | CQL spec 3.2.0 | Native protocol v3]
Use HELP for help.
cqlsh DESCRIBE KEYSPACES
empty
cqlsh create keyspace foobar with replication =
{'class':'SimpleStrategy',
'replication_factor':3};
errors={}, last_host=192.168.0.2
cqlsh DESCRIBE KEYSPACES;
empty
cqlsh use foobar;
cqlsh:foobar DESCRIBE TABLES;
Keyspace 'foobar' not found.
Just trying cassandra 2.1 and encounter the above erorr, can anyone
explain
why is this and where to even begin troubleshooting?
Jason
--
Tyler Hobbs
DataStax http://datastax.com/
Re: Many really small SSTables
Hi, just as a short follow up, it worked - all nodes now have 20-30 sstables instead of thousands. Cheers, Roland
Re: Compaction failing to trigger
It's set on all the tables, as I'm using the default for all the tables. But for that particular table there are 41 SSTables between 60MB and 85MB, it should only take 4 for the compaction to kick in. As this is probably a bug and going back in the mailing list archive, it seems it's already been reported: - Is there a workaround? - What is the JIRA ticket number? - Will it be fixed in 2.1.3? Thanks Flavien On 19 January 2015 at 01:23, 严超 yanchao...@gmail.com wrote: Seems like Size Tier Compaction is based on table, which table did you set the compaction strategy? A minor compaction does not involve all the tables in a keyspace. Ref: http://datastax.com/documentation/cassandra/2.0/cassandra/operations/ops_configure_compaction_t.html http://datastax.com/documentation/cql/3.1/cql/cql_reference/tabProp.html?scroll=tabProp__moreCompaction *Best Regards！* *Chao Yan--**My twitter：Andy Yan @yanchao727 https://twitter.com/yanchao727* *My Weibo：http://weibo.com/herewearenow http://weibo.com/herewearenow--* 2015-01-19 3:51 GMT+08:00 Flavien Charlon flavien.char...@gmail.com: Hi, I am using Size Tier Compaction (Cassandra 2.1.2). Minor compaction is not triggering even though it should. See the SSTables on disk: http://pastebin.com/PSwZ5mrT You can see that we have 41 SSTable between 60MB and 85MB, which should trigger compaction unless I am missing something. Is that a bug? Thanks, Flavien
Re: number of replicas per data center?
3 what? :-P replicas per datacenter or 3 data centers? So if you have 2 data centers you would have 6 total replicas with 3 local replicas per datacenter? On Sun, Jan 18, 2015 at 7:53 PM, Jonathan Haddad j...@jonhaddad.com wrote: Personally I wouldn't go 3 unless you have a good reason. On Sun Jan 18 2015 at 7:52:10 PM Kevin Burton bur...@spinn3r.com wrote: How do people normally setup multiple data center replication in terms of number of *local* replicas? So say you have two data centers, do you have 2 local replicas, for a total of 4 replicas? Or do you have 2 in one datacenter, and 1 in another? If you only have one in a local datacenter then when it fails you have to transfer all that data over the WAN. -- Founder/CEO Spinn3r.com Location: *San Francisco, CA* blog: http://burtonator.wordpress.com … or check out my Google+ profile https://plus.google.com/102718274791889610666/posts http://spinn3r.com -- Founder/CEO Spinn3r.com Location: *San Francisco, CA* blog: http://burtonator.wordpress.com … or check out my Google+ profile https://plus.google.com/102718274791889610666/posts http://spinn3r.com
Re: keyspace not exists?
Hi, Immediately after a repair, I execute cqlsh, still the schema mismatch? [2015-01-19 13:50:49,979] Repair session 19c67350-9f9f-11e4-8b56-a322c40b8b81 for range (-725731847063341791,-718486959589605925] finished [2015-01-19 13:50:49,980] Repair session 1a612cb0-9f9f-11e4-8b56-a322c40b8b81 for range (-5366440687164990017,-5357952536457207248] finished [2015-01-19 13:50:49,980] Repair session 1afcd070-9f9f-11e4-8b56-a322c40b8b81 for range (-2871651679602006497,-2860883420245139806] finished [2015-01-19 13:50:49,980] Repair session 1b99acb0-9f9f-11e4-8b56-a322c40b8b81 for range (-394095345040964045,-391878264832686281] finished [2015-01-19 13:50:49,981] Repair session 1c352960-9f9f-11e4-8b56-a322c40b8b81 for range (8830377476646048271,8848086816619852308] finished [2015-01-19 13:50:49,981] Repair session 1cd1de90-9f9f-11e4-8b56-a322c40b8b81 for range (4538653889569069241,4549572313549299652] finished [2015-01-19 13:50:49,985] Repair session 1d6ebad0-9f9f-11e4-8b56-a322c40b8b81 for range (6052068628404624993,6058413940102734921] finished [2015-01-19 13:50:49,986] Repair command #1 finished jason@localhost:~$ cqlsh 192.168.0.2 9042 Warning: schema version mismatch detected; check the schema versions of your nodes in system.local and system.peers. Connected to just4fun at 192.168.0.2:9042. [cqlsh 5.0.1 | Cassandra 2.1.1 | CQL spec 3.2.0 | Native protocol v3] Use HELP for help. cqlsh cqlsh desc keyspaces; system_traces jw_schema1 system cqlsh use jw_schema1; cqlsh:jw_schema1 desc tables; user_profiles cqlsh:system select host_id,schema_version from system.peers; host_id | schema_version --+-- d21e3d11-5bfb-4888-97cd-62af90e83f56 | b5291c1d-6635-3627-928f-f5a0f0c27ec1 d21e3d11-5bfb-4888-97cd-62af90e83f56 | c7a2ebda-89f7-36f0-a735-a0dffc400124 69bd2306-c919-411b-83f3-341b4f7f54b4 | f6f3835e-ed12-34f4-9f4b-f2a72bb57c30 e1444216-4412-45d5-9703-a463ee50aec2 | f6f3835e-ed12-34f4-9f4b-f2a72bb57c30 (4 rows) cqlsh:system select host_id,schema_version from system.local; host_id | schema_version --+-- d21e3d11-5bfb-4888-97cd-62af90e83f56 | f6f3835e-ed12-34f4-9f4b-f2a72bb57c30 (1 rows) On Mon, Jan 19, 2015 at 12:55 PM, Jason Wee peich...@gmail.com wrote: log does not show anything fishy, because it is just for fun cluster, we can actually wipe our 3 nodes cluster casandra dir, data,saved_caches,commitlog and start it all over, we encounter the same problem. two nodes running cassandra 2.1.2 and one running cassandra 2.1.1 I look a look at the issue given by Tyler link, and patch my cqlsh and given more information below and thank you it works. Actually doing this tutorial from this blog http://www.datastax.com/dev/blog/thrift-to-cql3 $ cqlsh 192.168.0.2 9042 Warning: schema version mismatch detected; check the schema versions of your nodes in system.local and system.peers. Connected to just4fun at 192.168.0.2:9042. [cqlsh 5.0.1 | Cassandra 2.1.1 | CQL spec 3.2.0 | Native protocol v3] Use HELP for help. cqlsh DESCRIBE KEYSPACES; system_traces jw_schema1 system cqlsh use jw_schema1; cqlsh:jw_schema1 desc tables; user_profiles cqlsh:jw_schema1 quit; $ cassandra-cli -h 192.168.0.2 -p 9160 Connected to: just4fun on 192.168.0.2/9160 Welcome to Cassandra CLI version 2.1.1 The CLI is deprecated and will be removed in Cassandra 3.0. Consider migrating to cqlsh. CQL is fully backwards compatible with Thrift data; see http://www.datastax.com/dev/blog/thrift-to-cql3 Type 'help;' or '?' for help. Type 'quit;' or 'exit;' to quit. [default@unknown] show keyspaces; WARNING: CQL3 tables are intentionally omitted from 'show keyspaces' output. See https://issues.apache.org/jira/browse/CASSANDRA-4377 for details. Keyspace: jw_schema1: Replication Strategy: org.apache.cassandra.locator.SimpleStrategy Durable Writes: true Options: [replication_factor:3] Column Families: ColumnFamily: user_profiles Key Validation Class: org.apache.cassandra.db.marshal.UTF8Type Default column value validator: org.apache.cassandra.db.marshal.BytesType Cells sorted by: org.apache.cassandra.db.marshal.UTF8Type GC grace seconds: 864000 Compaction min/max thresholds: 4/32 Read repair chance: 0.0 DC Local Read repair chance: 0.1 Caching: KEYS_ONLY Default time to live: 0 Bloom Filter FP chance: 0.01 Index interval: default Speculative Retry: 99.0PERCENTILE Built indexes: [] Column Metadata: Column Name: first_name Validation Class: org.apache.cassandra.db.marshal.UTF8Type Column Name: year_of_birth Validation Class: org.apache.cassandra.db.marshal.Int32Type Column Name: last_name Validation Class:
Re: Compaction failing to trigger
Hi Flavien,
I hit some problem with minor compations recently (just some days ago) -
but with many more tables. In my case compactions got not triggered, you
can check this with nodetool compactionstats.
Reason for me was that those minor compactions did not get triggered
since there were almost no reads on that tables. Setting
'cold_reads_to_omit' to 0 did the job for me:
ALTER TABLE tablename WITH compaction = {'class':
'SizeTieredCompactionStrategy', 'min_threshold': '4', 'max_threshold': '32',
'cold_reads_to_omit': 0.0};
Credits to Tyler and Eric for the pointers.
Cheers,
Roland
Re: number of replicas per data center?
Sorry, I left out RF. Yes, I prefer 3 replicas in each datacenter, and that's pretty common. On Sun Jan 18 2015 at 8:02:12 PM Kevin Burton bur...@spinn3r.com wrote: 3 what? :-P replicas per datacenter or 3 data centers? So if you have 2 data centers you would have 6 total replicas with 3 local replicas per datacenter? On Sun, Jan 18, 2015 at 7:53 PM, Jonathan Haddad j...@jonhaddad.com wrote: Personally I wouldn't go 3 unless you have a good reason. On Sun Jan 18 2015 at 7:52:10 PM Kevin Burton bur...@spinn3r.com wrote: How do people normally setup multiple data center replication in terms of number of *local* replicas? So say you have two data centers, do you have 2 local replicas, for a total of 4 replicas? Or do you have 2 in one datacenter, and 1 in another? If you only have one in a local datacenter then when it fails you have to transfer all that data over the WAN. -- Founder/CEO Spinn3r.com Location: *San Francisco, CA* blog: http://burtonator.wordpress.com … or check out my Google+ profile https://plus.google.com/102718274791889610666/posts http://spinn3r.com -- Founder/CEO Spinn3r.com Location: *San Francisco, CA* blog: http://burtonator.wordpress.com … or check out my Google+ profile https://plus.google.com/102718274791889610666/posts http://spinn3r.com
Re: number of replicas per data center?
Personally I wouldn't go 3 unless you have a good reason. On Sun Jan 18 2015 at 7:52:10 PM Kevin Burton bur...@spinn3r.com wrote: How do people normally setup multiple data center replication in terms of number of *local* replicas? So say you have two data centers, do you have 2 local replicas, for a total of 4 replicas? Or do you have 2 in one datacenter, and 1 in another? If you only have one in a local datacenter then when it fails you have to transfer all that data over the WAN. -- Founder/CEO Spinn3r.com Location: *San Francisco, CA* blog: http://burtonator.wordpress.com … or check out my Google+ profile https://plus.google.com/102718274791889610666/posts http://spinn3r.com
Re: number of replicas per data center?
I like to have 3 replicas across 3 racks in each datacenter as a rue of thumb. You can vary that, but it depends upon the use case, and the SLA's for latency. This can get a little complicated if you're using the cloud and automated deployment strategies as I like to use the same abstractions externally as internally. -- Colin Clark +1-320-221-9531 On Jan 18, 2015, at 9:49 PM, Kevin Burton bur...@spinn3r.com wrote: How do people normally setup multiple data center replication in terms of number of *local* replicas? So say you have two data centers, do you have 2 local replicas, for a total of 4 replicas? Or do you have 2 in one datacenter, and 1 in another? If you only have one in a local datacenter then when it fails you have to transfer all that data over the WAN. -- Founder/CEO Spinn3r.com Location: San Francisco, CA blog: http://burtonator.wordpress.com … or check out my Google+ profile
Re: Which files should I backup for data restoring/data migration?
Check out this doc, I think it may help you: http://www.datastax.com/documentation/cassandra/2.0/cassandra/operations/ops_backup_restore_c.html *Best Regards！* *Chao Yan--**My twitter：Andy Yan @yanchao727 https://twitter.com/yanchao727* *My Weibo：http://weibo.com/herewearenow http://weibo.com/herewearenow--* 2015-01-18 21:06 GMT+08:00 孔嘉林 kongjiali...@gmail.com: Hi, I want to backup the files needed for data restoring/data migration. There are several directories: /var/lib/cassandra/ - commitlog/ - data/ - mytable/ - system/ - system_traces/ - saved_caches/ /var/log/cassandra/ So if I want a new machine start cassandra service on having the old data, which of the files are needed? Is only the /var/lib/cassandra/data/mytable/ directory enough? Or I should copy all of the above files on the new machine? Thanks very much, Joy
Re: Compaction failing to trigger
Seems like Size Tier Compaction is based on table, which table did you set the compaction strategy? A minor compaction does not involve all the tables in a keyspace. Ref: http://datastax.com/documentation/cassandra/2.0/cassandra/operations/ops_configure_compaction_t.html http://datastax.com/documentation/cql/3.1/cql/cql_reference/tabProp.html?scroll=tabProp__moreCompaction *Best Regards！* *Chao Yan--**My twitter：Andy Yan @yanchao727 https://twitter.com/yanchao727* *My Weibo：http://weibo.com/herewearenow http://weibo.com/herewearenow--* 2015-01-19 3:51 GMT+08:00 Flavien Charlon flavien.char...@gmail.com: Hi, I am using Size Tier Compaction (Cassandra 2.1.2). Minor compaction is not triggering even though it should. See the SSTables on disk: http://pastebin.com/PSwZ5mrT You can see that we have 41 SSTable between 60MB and 85MB, which should trigger compaction unless I am missing something. Is that a bug? Thanks, Flavien
Re: Not enough replica available” when consistency is ONE?
OK.. so if I’m running with 2 replicas, then BOTH of them need to be online for this to work. Correct? Because with two replicas I need 2 to form a quorum. This is somewhat confusing them. Because if you have two replicas, and you’re depending on these types of transactions, then this is a VERY dangerous state. Because if ANY of your Cassandra nodes goes offline, then your entire application crashes. So the more nodes you have, the HIGHER the probability that your application will crash. Which is just what happened to me. And in retrospect, this makes total sense, but of course I just missed this in the application design. So ConsistencyLevel.ONE and if not exists are essentially mutually incompatible and shouldn’t the driver throw an exception if the user requests this configuration? Its dangerous enough that it probably shouldn’t be supported. On Sun, Jan 18, 2015 at 7:43 AM, Eric Stevens migh...@gmail.com wrote: Check out http://www.datastax.com/documentation/cassandra/2.0/cassandra/dml/dml_tunable_consistency_c.html Cassandra 2.0 uses the Paxos consensus protocol, which resembles 2-phase commit, to support linearizable consistency. All operations are quorum-based ... This kicks in whenever you do CAS operations (eg, IF NOT EXISTS). Otherwise a cluster which became network partitioned would end up being able to have two separate CAS statements which both succeeded, but which disagreed with each other. On Sun, Jan 18, 2015 at 8:02 AM, Kevin Burton bur...@spinn3r.com wrote: I’m really confused here. I”m calling: acquireInsert.setConsistencyLevel( ConsistencyLevel.ONE ); but I”m still getting the exception: com.datastax.driver.core.exceptions.UnavailableException: Not enough replica available for query at consistency SERIAL (2 required but only 1 alive) Does it matter that I’m using: ifNotExists(); and that maybe cassandra needs two because it’s using a coordinator ? If so then an exception should probably be thrown when I try to set a wrong consistency level. which would be weird because I *do* have at least two replicas online. I have 4 nodes in my cluster right now... -- Founder/CEO Spinn3r.com Location: *San Francisco, CA* blog: http://burtonator.wordpress.com … or check out my Google+ profile https://plus.google.com/102718274791889610666/posts http://spinn3r.com -- Founder/CEO Spinn3r.com Location: *San Francisco, CA* blog: http://burtonator.wordpress.com … or check out my Google+ profile https://plus.google.com/102718274791889610666/posts http://spinn3r.com
Not enough replica available” when consistency is ONE?
I’m really confused here. I”m calling: acquireInsert.setConsistencyLevel( ConsistencyLevel.ONE ); but I”m still getting the exception: com.datastax.driver.core.exceptions.UnavailableException: Not enough replica available for query at consistency SERIAL (2 required but only 1 alive) Does it matter that I’m using: ifNotExists(); and that maybe cassandra needs two because it’s using a coordinator ? If so then an exception should probably be thrown when I try to set a wrong consistency level. which would be weird because I *do* have at least two replicas online. I have 4 nodes in my cluster right now... -- Founder/CEO Spinn3r.com Location: *San Francisco, CA* blog: http://burtonator.wordpress.com … or check out my Google+ profile https://plus.google.com/102718274791889610666/posts http://spinn3r.com
Re: Not enough replica available” when consistency is ONE?
Check out http://www.datastax.com/documentation/cassandra/2.0/cassandra/dml/dml_tunable_consistency_c.html Cassandra 2.0 uses the Paxos consensus protocol, which resembles 2-phase commit, to support linearizable consistency. All operations are quorum-based ... This kicks in whenever you do CAS operations (eg, IF NOT EXISTS). Otherwise a cluster which became network partitioned would end up being able to have two separate CAS statements which both succeeded, but which disagreed with each other. On Sun, Jan 18, 2015 at 8:02 AM, Kevin Burton bur...@spinn3r.com wrote: I’m really confused here. I”m calling: acquireInsert.setConsistencyLevel( ConsistencyLevel.ONE ); but I”m still getting the exception: com.datastax.driver.core.exceptions.UnavailableException: Not enough replica available for query at consistency SERIAL (2 required but only 1 alive) Does it matter that I’m using: ifNotExists(); and that maybe cassandra needs two because it’s using a coordinator ? If so then an exception should probably be thrown when I try to set a wrong consistency level. which would be weird because I *do* have at least two replicas online. I have 4 nodes in my cluster right now... -- Founder/CEO Spinn3r.com Location: *San Francisco, CA* blog: http://burtonator.wordpress.com … or check out my Google+ profile https://plus.google.com/102718274791889610666/posts http://spinn3r.com
Which files should I backup for data restoring/data migration?
Hi, I want to backup the files needed for data restoring/data migration. There are several directories: /var/lib/cassandra/ - commitlog/ - data/ - mytable/ - system/ - system_traces/ - saved_caches/ /var/log/cassandra/ So if I want a new machine start cassandra service on having the old data, which of the files are needed? Is only the /var/lib/cassandra/data/mytable/ directory enough? Or I should copy all of the above files on the new machine? Thanks very much, Joy
Compaction failing to trigger
Hi, I am using Size Tier Compaction (Cassandra 2.1.2). Minor compaction is not triggering even though it should. See the SSTables on disk: http://pastebin.com/PSwZ5mrT You can see that we have 41 SSTable between 60MB and 85MB, which should trigger compaction unless I am missing something. Is that a bug? Thanks, Flavien
