Re: Experts,Please Ur Kind Input here

Ibrahim Jamil · ‎03-08-2011

Hi Folks

I Have 4 Mbps MPLS Link between Two Sites , I Received Complain from the Data Base Administrator ,there is a Delay and Latency appears on Logs when the database Replication occurs

Please Help to solve this issue

rtjensen4 · ‎03-08-2011

Soooo....

What have you done to being troubleshooting this?

1. Check utilization on both ends of the link

2. Check errors on the links.

3. What does the latency / delay look like if you do a db replication at the LAN vs across the WAN

4. Are you doing any prioritization?

5. Is there heavy traffic elsewhere in your LAN at either location that could be causing this

6. Any overloaded devices?

Ibrahim Jamil · ‎03-08-2011

Hi

Thanks for your reply,can u expain the blow:

5.Is there heavy traffic elsewhere in your LAN at either location that could be causing this

6. Any overloaded devices?

How to verify the below:

1. Check utilization on both ends of the link

2. Check errors on the links.

3. What does the latency / delay look like if you do a db replication at the LAN vs across the WAN

4. Are you doing any prioritization?

Kishore Chennupati · ‎03-08-2011

Hi Ibrahim,

How to verify the below:

1. Check utilization on both ends of the link

Normally you can use tools to grpah your traffic etc lik MRTG graphs, Cacti

However on the CLI you can issue the "sh interface | i rate" depending on your device and interface.

This shows you the 5 minute average intervals. You can change to lower interval say like 30 seconds as well

2. Check errors on the links.

Again , sh interface will show the crc, giants, runts depending on what interface your using

3. What does the latency / delay look like if you do a db replication at the LAN vs across the WAN

This will isolate if the issue is the DB server itself cause sometimes the DB server might be too busy to receive TCP connections etc.

4. Are you doing any prioritization?

This is related to Qos. meaning are you classifying any traffic as important and proritizing it.

HTH

Regards,

Please rate if helpful

Ibrahim Jamil · ‎03-09-2011

.

Hi Kishore

Can you Explain the Below:

This will isolate if the issue is the DB server itself cause sometimes the DB server might be too busy to receive TCP connections etc.

regarding qos how to mark this sql traffic ,is it dscp AF31?also sql traffic its UDP or TCP?

what to tell the mpls provider in order to guarantees sql traffic as missin critical data

Kishore Chennupati · ‎03-09-2011

Hi Ibrahim,

This will isolate if the issue is the DB server itself cause sometimes the DB server might be too busy to receive TCP connections etc.

This basically means to find out if the issue is with the DB server. If the DB server is busy then it will affect even the local site users as well. So this means that even the remote office users wil be affected.

regarding qos how to mark this sql traffic ,is it dscp AF31?also sql traffic its UDP or TCP?

depends on what you are using Sql uses both tcp and udp. you can set it to AF31 . that should be fine

http://en.wikipedia.org/wiki/List_of_TCP_and_UDP_port_numbers

what to tell the mpls provider in order to guarantees sql traffic as missin critical data

you need to work with the ISP to mark your traffic as mission critical. you need to buy Qos from them though

HTH,

Regards,

Kishore

Please rate if helpful

Ibrahim Jamil · ‎03-12-2011

Hi folks

How to verify the below:

5. Is there heavy traffic elsewhere in your LAN at either location that could be causing this

Kishore Chennupati · ‎03-13-2011

Hi Ibrahim,

5. Is there heavy traffic elsewhere in your LAN at either location that could be causing this

Normally you can use tools to grpah your traffic etc lik MRTG graphs, Cacti

However on the CLI you can issue the "sh interface | i rate|broad" depending on your device and interface.

This shows you the 5 minute average intervals. You can change to lower interval say like 30 seconds as well

Also, please check the utilisation and memory as well on the devices using " sh proc cpu sorted" and "sh proc mem sorted"

HTH

Regards,

Kishore

Please rate if helpful