I am following the documents about how to restore Redis and I am at complete loss at this point.
The document says
127.0.0.1:6379> SAVE
OK
This command will create the dump.rdb file in your redis directory.
Which it does, it creates the exact same file for me in /usr/lib/redis which is alright I guess.
To restore redis data just move redis backup file (dump.rdb) into your redis directory and start the server. To get your redis directory use CONFIG command can be used. The CONFIG GET command is used to read the configuration parameters of a running Redis server.
127.0.0.1:6379> CONFIG get dir
1) "dir"
2) "/var/lib/redis/6379"
Here is where it makes no sense to me. The .rdb file for me is already saved in /var/lib/redis/ and I have no sub folder to that. I don't understand what "dir" is doing there and how I can restore my database.
Please enlighten me. I don't seem to be able to save it or I cannot find it perhaps.
Okay so basically, the rdb file saved in /var/lib/redis/ is saved every time the server stops and this can be moved to another folder and be used as a point for restoring every time redis service starts.
Related
We have encountered a weird redis issue.
After I upgrade my redis from an old version to a new one,
I bring up the redis with clean data.
I copied the previous rdb file into the data direcotry
I restart the redis to load the data.
THen, I figure that my data is wiped out in step 4. Do any of you have encounter this? What could be the possible root cause for this?
We are suspect the redis is getting new request for it. Will that be an possible issue?
Before shutting down Redis will persist its data to disk (unless it is completely disabled in config), so you should not try such "hot swapping" of RDB file while Redis server is running - as it simply has overwritten the file on exit. Instead, just stop Redis server and replace RDB file to get it loaded (and later saved back properly).
I remember playing around with some settings and I believe it changed the location of dump.rdb. Now, dump.rdb auto-magically appears at the root of my projects.
Where does it belong, and how would I return it there? Also, how does this location change when in a production environment?
Where does it belong?
Wherever you want.
The default directory is ./, meaning the directory where the Redis server got started from.
Edit:
* I am modifying your second question (asked in comment) a little bit.
Is it possible to change to location of dump.rdb? How?
Yes, it is possible. There two possible ways I can think of.
1.
Modify redis configuration file (e.g. redis.conf) and restart redis server. This way, every restart after this one will use the new directory. But redis will not reload any previous data at first restart (because there will not be anything to reload from).
To reload previous data, previous dump.rdb would have to be moved to new location manually before restarting the server.
2.
Set new directory by CONFIG SET command. E.g.
CONFIG SET dir path/to/new/directory
* Note that the path has to be a directory.
That's it! But this way is not permanent because server restart will use the old directory.
To make new directory permanent, execute CONFIG REWRITE to rewrite the configuration file. Remember, redis server has to have write permission to that file.
dir path/to/dorectory has to be set in the redis config file.
I have my redis server in my local and when i copy those contents with dump.rdb bgsave and put it in my other machine .Every thing works fine but after some inactivity my keys keep getting deleted and I'm ending up with 433KB of dump file and my dump file being replaced.What am i doing wrong?I have 3.0.3 in local and 2.8.4 in my other machine.I am following steps from this [link][1]. I couldn't able to figure out this issue.I checked the server logs and there's no error there just only those bgsaves for every 900,300 seconds.Please Help me
Most commonly this is probably because
Your Redis instance is open to a public network and isn't using password authentication - crackers can do anything for deleting your keys to compromising the server.
All your keys are set to expire
You are using an eviction policy such as all-keys, your maxmemory is set and you've reached it.
You have a rogue piece of code that deletes them.
I use Redis, and today I start to get the following exception:
Can't save in background: fork: Cannot allocate memory
As I understand, this error appears because my DB is too big, and there is no memory for this process.
So I start to delete tables, but the problem is that Redis doesn't success to write it to the disc, and in face it doesn't know about this changes.
I decided to create new .rdb file (in /etc/redis.config), and then change the file path with the new RDB file:
dbfilename dump_cache_new.rdb
Then, I will reload all the data which critical to me (I can do it - its data from my file system), and restart redis service.
The problem is that I can't create this file, because redis is now executing with the old path (and Redis has to run, because other process takes some critical data from it).
How can I create this dump_cache_new.rdb file, while redis is still running with the old path?
If you want to change the snapshot file name (or most other configuration parameters) on a running instance of Redis, use the CONFIG SET command. Based on that documentation page, it looks like dir and dbfilename are both parameters than can be set on a live instance.
Another option to consider is using the synchronous SAVE command, which doesn't require a fork.
You almost never want to call SAVE in production environments where it will block all the other clients. Instead usually BGSAVE is used. However in case of issues preventing Redis to create the background saving child (for instance errors in the fork(2) system call), the SAVE command can be a good last resort to perform the dump of the latest dataset.
It's a pretty severe operation, but if you're already at the point of dumping data to make the save work, this would at least allow you to first make a snapshot.
I am using Redis since last 12 months without any issue, But from last 30 days unknowingly the database getting empty and we couldn't find any logs regarding this. Even it is flushing all the data out randomly after restoration.
We tried following steps to resolve this but result was zero.
We have checked redis logs
Monitored the redis using MONITOR command
We are trying to renaming the critical commands through config but redis is dump after the config change below is example command
rename-command FLUSHDB e0cc96ad2eab73c2c347011806a76b73
We gone made without knowing anything. Helps are appreciated.
Redis Version : 2.8.17
Running under Debian Linux
Renaming the command through config file will work in this case.
Same rename command you have to place inside the config file.
rename-command FLUSHDB e0cc96ad2eab73c2c347011806a76b73