AIX

Hi All.

We are using AIX 5.3 ML9. There is 1 Gig NIC installed on two servers (Primary and Secondary) with Full Duplex Mode. We have scheduled a cronjob to copy the backup from primary to secondary thru FTP on WAN. The total data size is 15 GB and it took 9 Hours and 18 Mins with transfer rate as 700Kb/Sec. The bandwidth between Primary and Secondary is 30Mbps.

When we ask ISP to remove the bandwidth restriction from the link the same data FTP in just 20 Mins with transfer rate as 11Mbps/Sec

I would like to know if is there any OS Parameters to speed up the FTP.
Regards,

Hassan

I think all you could do to improve the speed with the WAN bandwidth restriction in place would be to either only do incremental backups most of the time or to explore data compression on the primary before you send it.
If it is a normal backup then experiment with using pax and then compress to see it you can make it much smaller before you send it.
It seems the real restriction is the WAN bandwidth so the only way to overcome this will be to send less data.

We have compressed the data before FTP, we use gzip to compress. Also note that the data contains multiple files sized 500 MB, 200 MB, 100MB. The Communication vendor has asked to check if there is any OS Parameter to set the bandwidth restriction used by FTP or any other process.

Kindly also note that there is no process executing when we FTP the backup.

lodhi1978 Will be interesting if you try to upload this files using SSH... If the speed would be the same than the problem really exists at provider site...

A 100 megabit connection should top out around 12 MB/s. A 1000 megabit connection should top out around 120 MB/s. It seems suspicious that you are only seeing 11 MB/s, like you may only be running at 100 mpbs.

Are you connecting to a gigabit switch and is it configured for a gigabit connection? Your connection may be auto-negotiating to only a 100 mbps connection. I'm not sure how you can check the negotiated speed from within AIX but the switch people can tell you for sure from their side.

We have also tried sftp and found the same result as ftp.

The NIC configuration on both the servers as below:
Media Speed Selected: 1000 Mbps Full Duplex
Media Speed Running: 1000 Mbps Full Duplex

We have also tried to Auto-Negotiate, but there is no improvement.

lodhi1978 I recommend to take any notebook with simple windows or Linux installed
configure any simple ftp server for example vsftpd and try again to upload some files, and also I woud recommend to set users unlimited in /etc/security/limits like this:

Code:

 default:
        fsize = -1
        core = -1
        cpu = -1
        data = -1
        rss = -1
        stack = -1
        nofiles = -1

if the speed will be the same than provider has to look in their Router QOS configuration and it will show if some packets from your site are discarded due to the bandwidth restriction