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I currently work for MongoDB, Inc. and have a background in operations, networking and system administration. You can find me in all the usual places, but probably the most useful and relevant are listed below:

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Dec
16
comment adding mongodb authentication breaks connecting via nodejs
two things: First, please post a code sample so that (at a minimum) others can try this out and debug. Second, can you connect with that user from the shell and run the operations you want from the shell? Finally, if this a code issue, then this may be more appropriate for StackOverflow than Serverfault
Oct
7
comment Background indexing MongoDB on server
for reference, you can check to see if the index build is still running on the mongod by running db.currentOp() from the mongo shell or by looking in the logs for that instance (it will log index build progress periodically and give you a percentage completion figure).
Oct
1
comment How to start Mongo daemon with auth support
You should ask a new question and detail what versions (of OS, MongoDB) you are using, the error you are getting, and what your config looks like. There was no problem when I did the procedure above, so it's basically likely that the problem was user error or similar since the issue is not reproducible.
Sep
14
comment mongodb keep looping while trying to sync data
ulimits might be the cause, if the primary is seeing a significant number of connections - the best way to find out is to increase the number and see if that solves the issue (or look at the available connections in db.serverStatus(). Without some detailed troubleshooting all we can do is guess at the root cause of the connection problems
Sep
8
comment How to construct a MongoDB Health Check in HAProxy?
And I must have had a typo when I did my original partial binary check (which led me to believe it did not work). I have edited (and attributed) to reflect this, and added my successful binary check for good measure - thanks for the help. @Baptiste - the answer probably makes more sense as a comment, so I would suggest removing it - or you can edit to make it correct (s/string/binary/) to make it less confusing if someone does read through in the future.
Sep
2
comment How to construct a MongoDB Health Check in HAProxy?
Retested with tcp-check expect string 6f6b and the health check is now failing, so "ok" looks like the correct way to go for the MongoDB case
Sep
2
comment How to construct a MongoDB Health Check in HAProxy?
Confirmed that a string check of "ok" does work with my example (checked with mongod, mongos and made sure HAProxy marked them as UP), "ok" is found in the response as a string 6f6b is just the hex/ASCII representation of ok in any case, so it's the same match. I thought that "ok" made more sense since it is listed as a string match, not binary (and a binary match fails because it tries to match the whole buffer I believe)
Aug
10
comment Mongodb replica failures to resolve DNS when primary DNS is stopped while secondary DNS is operational
Just to note, the question is misleading because that's not a crash - it's just a failure to resolve the address because it's not failing over to the secondary DNS - a crash would mean that the mongod completely shuts down which is not happening here (and would mean something very different)
Jul
10
comment MongoDB Max Connections
Can you comment on the version you are using - the treatment of max connections changed with 2.6
Jun
26
comment MongoDB copyDatabase failed with dbOwner
My bad - it even tells you that the data remains intact at the end of that page. Seems that is the issue, so need to figure out a way to get rid of that permanently (assuming no issues post-migration)
Jun
26
comment MongoDB copyDatabase failed with dbOwner
Did you do this when you upgraded? docs.mongodb.org/manual/release-notes/2.6-upgrade-authorization There is a process to upgrade the user auth data when you go to 2.6 - if you did this and the issue is still there, then it's probably a (reproducible) bug, but if not then that is likely the root cause here.
Jun
25
comment MongoDB copyDatabase failed with dbOwner
Try: { resource: { db: "db1", collection: "system.users" }, actions: [ "find" ] } and then add insert to the actions if it still fails.
Jun
25
comment MongoDB copyDatabase failed with dbOwner
Hmmm, since this is not an admin DB you shouldn't need access to system.users and dbOwner should be more than enough. That makes me wonder if the authentication is succeeding and granting you that role for the copyDatabase. It will take me a little while to get some testing set up. If you wanted to do a little differential diagnosis yourself in the meantime, you could try using the root role for that user temporarily and see if it still fails. If it does, then that would imply that the issue is getting authenticated as the user rather than the role the user has (root has all access)
Jun
25
comment ENTRYPOINT & CMD commands with mongod results in unknown option error
first thing to try would be to take out the port and dbpath parameters, after all that is what you get as defaults anyway. What happens if you make it just CMD ["--smallfiles"]?
Jun
23
comment mongod won't run without me specifying my own conf path
I don't think you quite got what I meant. When you run mongod with not arguments, it defaults to /data/db - that will error regardless of the user you are running with if that folder does not exist. Hence your issues when running it without an explicit dbpath or config. Your issue with the service starting, and then not working is separate, and that is where you are likely running afoul of the permissions issues. None of this is really a mongodb issue, you would have the same problems with any service's files if you run the service as root.
May
30
comment Mongodump on Gridfs is killing the host IOs
Not at the moment, unless you use a node specifically for that purpose - you could have a secondary and tag it as "backup", the others as "prod" for example and have the backup queries only hit that node. You could even run more than one process on the host, make one of the them your designated backup node and then ionice that process, but for a single existing process there is no way to target specific queries within that process from a system level (that I know of).
May
30
comment Mongodump on Gridfs is killing the host IOs
But, since all the requests are coming from the same binary (mongod) you can't use ionice - the mongodump uses a regular query just like anything else and that is then serviced by mongod, so it's not competing with another process. You can use mongodump to access files directly (and hence ionice would work on it) but you have to shut down the mongod to be able to do that anyway, so nothing gained.
Apr
14
comment Backup MongoDB database copying files in `dbpath`?
Asked and answered already here: dba.stackexchange.com/a/62853/6441
Apr
8
comment how to integrate between MONGODB & SOLR, using MONGO-CONNECTOR
auth is failing (per the error) - if you run without auth I assume it will work, so it would seem that you are either passing in the wrong credentials or the user is not valid to run the command - you mentioned that you started the shell, but did you try running a command (like rs.status()) to verify the user was logged in and valid?
Apr
3
comment Did my mongoDB server crash because the database is too large?
@Tim - mongodb has a max file size of 2GB for that reason (some FS/OS not supporting it) - it pre-allocates multiple files of 2GB (max, starts smaller) when databases exceed that size (see your data directory for database.0, database.1 etc.)