I am trying to add remote slave to my master. The master is behind firewall. how can one add the remote slave to this master. do I have to open a new port ? if yes will master.cfg file will have two port number ? c['slavePortnum'] = 9989
Can anyone please help me in this regard. My question might not be clear because I my self dont know much about how to do this. I couple of slave that are within the network of master so I dont have to worry about the firewall but now I have to add remote slave I am worried that the connection might not happen because of the fire wall.
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MySQL Replication and myAppExample, which IP to point the app to? To the Master, Router, one of the slaves?
I setup a typical lamp stack and also a MySQL InnoDB cluster.
myAppExample: 10.3.1.9
mysql-0 : 10.3.1.10
mysql-1 : 10.3.1.11
mysql-2 : 10.3.1.12
mysql-router: 10.3.1.13
What is the norm, best practice, or intended use of the replication method?
Should I point my myAppExample to the mysql-0 (master), or to the Router? Or to one of the slaves?
I would think to point it to the router, so the cluster will route traffic to read or write accordingly for performance.
Do I point it to the router or to the master?
Thank you.
I've never done this, and I can't find documentation anywhere where to point the app after you set it up.
Solved.
There are a few questions here, let me address each of them.
You must point your myAppExample to the Router, not to node 0(master), nor other nodes 1,2,3,etc(slaves).
Yes, the app will refuse the connection to the mysql router, say it's at 10.3.1.12.
Connection works to the master(node-0), 10.3.1.9, since it looks for port 3306 by default.
You must specify which port to connect to the router, it's not port 3306, it's port 6446,
So in your app, you connect to your mysql server(actually the router), like this, 10.3.1.12:6446
I have a number of identical local postgreSql databases (identical in structure - not data) on several laptops that have intermittant access to internet. Records are being added to each DB daily. So Branch A,B,C each with a local Postgresql database. I would like all records from A,B,C in each table in a cloud Database.Also A,B,C data is separate - there is no overlap - A doesnt change B, or C etc. There are no duplicated unique keys.
NEED: I would like to collect all this data on a cloud based database by adding daily incremental data to a single cloud databse - so I can query the whole consolidated data using SQL and pull reports as needed.
Please can anyone point me in the right direction?
Thanks
It sounds like you want logical replication from each laptop to the cloud server. The problem there might be that contact must be made by the replica to each of the masters, so when your laptops are online, they would need to have predictable IP addresses so that they can be reached.
Maybe the best way around this is with a reverse SSH tunnel. On the central replica, you would tell it to subscribe to a publication hosted on some non-standard port on localhost. With a different port reserved for each laptop. So, for example, 9997, 9998, and 9999.
Then when each laptop has connectivity, it could run something like:
ssh rajb#1centralserver.example.com -R9999:localhost:5432 -f -N -T
This establishes an ssh connection to the central server (requiring a password, or private key, or however you have ssh set up) and sends instructions to the central server that whenever someone connects to port 9999 on the central server it should really send that connection back over ssh tunnel and hook it up to port 5432 (the default postgres server port) of the laptop.
For initially setting things up and debugging, you might want to omit the -f -N -T. That way, in addition to setting up the tunnel, you also get an interactive ssh session you can use for monitoring things.
Once the central service notices the connection is available, it will start downloading changes since the last time it could connect. When there is no connection, you will get a lot of nuisance messages to the log file as it checks each server every ~5 seconds to see if it is available.
From each laptop's perspective, the connection is coming from within, so the replication connection will use whatever authentication is set up or 127.0.0.1 or ::1, not the authentication set up for the actual remote IP.
In CA SCM Harvest Workbench, Version 12. 1..1.141 We face below error while check our or promoted. Not always but frequently. What should be done to overcome this issue? I tried to reinstall PEC in user matching, but it didn't fix it. Any solutions?
E0306003e: Could not connect to Broker: /pt_HBroker://r62dp10/0/haprd5 (Error Code = -307)
Error Code = -307 usually means that your SCM client cannot connect to your server. Look for network connectivity issues, e.g. try pinging server machine from client machine, try connecting to server:port via telnet. If you are an SCM administrator, ensure bkrd and rtserver are up and running. Otherwise, ask them.
If this happens just occasionally and stops happening by itself, there is probably some kind of problem in your network infrastructure, be it micro-cuts, noise, irregular latency...
I'm having a strange problem trying to maintain TCP connections from my local PC to Azure (oddly remote desktop works fine). I first noticed the problem with my own software, but it's not limited to it. What I've noticed is:
TCP 3 way handshake completes
Some data is successfully sent and received
Something bad happens and no more data is sent
To rule out my software, I tested netcat. On my Azure machine I set up a netcat server to echo a large text file. On my local PC I established the netcat connection to the Azure server and observed some of the text file being printed and then it just stopped.
The first Wireshark image is from the Azure server, and the second image is from my PC. Both were captured at the same time doing the netcat test I described above.
Here is my Azure endpoint configuration (same result with both endpoints):
I'm currently at a loss, and don't know enough about what the problem may be to continue my debugging efforts. Any suggestions would be greatly appreciated.
Thanks!
Some guy from Azure support told me that Azure Network's max. TCP packet size is 1350. So if your packets larger than this, it might be a problem. try to limit them to 1300 and test it again.
There are several things that could cause these kind of n/w problems such as below.
Azure SLB/SNAT
Azure Physical n/w issues(ACLs on Azure routers where your vms reside)
Proxies in front of your client applications etc.
We should systematically prune the problem space while tackling these kind of problems. For example, in this instance, you should run your client app on one of the Azure VMS and verify whether the issue is reproducible or not. If the issue is not reproducible, your problem must reside on your local pc n/w(or proxy behind which your machine resides) for 99% of time.
If you found the issue is reproducible from another Azure VM too, there must be something wrong on Azure side for 99% of time.
Some tips to identify issues on Azure side
Check whether your tcp connection is idle(not sending) data for 4 minutes. If that's the case, Azure SLB/SNAT layer drops the tcp connection on azure side. You could prevent this issue by either sending tcp keep alives or increasing vm endpoint idle time out using AzureEndpoint.
Hope this helps.
I am trying to setup a pptp server on Centos,
I open port 1723 (pptp port) with no issues when setting up pptp, and I do a nmap scan to confirm that it is open, however when I nmap the server remotely, it doesnt even list port 1723, by which I assume that port 1723 is not accesable
Is there something I am missing, forgetting
p.s., my first time setting up, so I am noob, please forgive any mistakes or missunderstandings and please dont down vote, I really need help and posting on serverfault apparently is of topic for this too...
UPDATE after #Calvin
Thank you for your informative response, do you know of anyway I can check where it is being blocked???
It is probably being blocked by a proxy server/firewall that the remote request has to go through. So for example, you're in one location A, wanting to connect to the other location B (which you've said is setup correctly and open to requests), though the security apparatus at location A have blocked outgoing requests to whatever port range, and likely outside your control unless you know the network administrators to check with them.
Is my first assumption.