Re: Correlating TCP connections with iSCSI connections

[Michael Christie]

On Aug 28, 2012, at 5:39 PM, Jeffrey Caughel <jcau...@gmail.com> wrote:

> In order to further dig into performance issues we're seeing, I am trying to correlate individual iSCSI connections with specific TCP connections. I don't want to negatively impact performance more than it already is so I was hoping to find a means for this that didn't require increasing the log level. I haven't found this recorded under /sys/class/iscsi_connection/connection[number] or under /var/lib/iscsi/nodes/[IQN]/[target_ip:port]/[interface]. I would expect it to be fairly simple and hopefully it's just eluding me - ultimately I would like to correlate this specific connection with an entry in `netstat -anvpt` that is itself associated with iscsid.
>

I don't think we have anything.

If you run iscsiadm -m session -P 2 you will see a "Iface IPaddress" value. This is the address that the iscsi connection uses on the local side, so it matches the ip address in the "Local Address" value in netstat. I could also print out the local port the iscsi connection is using so you could use both those values to match the address:port tuple you see in netstat "Local Address" field. Is that what you need?

[Mike Christie]

Ok. Let me try to get to this over the weekend.

On 08/28/2012 07:29 PM, Jeffrey Caughel wrote:
> That is exactly what I am looking for... peresently I can see something
> like this:
>
> # netstat -anpt
> <snip>
> tcp 0 48 192.168.0.155:60480 192.168.0.35:3260
> ESTABLISHED 5658/iscsid
> tcp 0 0 192.168.0.155:60452 192.168.0.35:3260
> ESTABLISHED 5658/iscsid
> tcp 0 48 192.168.0.155:60448 192.168.0.35:3260
> ESTABLISHED 5658/iscsid
> tcp 0 0 192.168.0.155:60460 192.168.0.35:3260
> ESTABLISHED 5658/iscsid
> tcp 0 0 192.168.0.155:60458 192.168.0.35:3260
> ESTABLISHED 5658/iscsid
> tcp 0 0 192.168.0.155:60466 192.168.0.35:3260
> ESTABLISHED 5658/iscsid
> tcp 0 0 192.168.0.155:60420 192.168.0.35:3260
> ESTABLISHED 5658/iscsid
> tcp 0 0 192.168.0.155:60422 192.168.0.35:3260
> ESTABLISHED 5658/iscsid
> tcp 0 0 192.168.0.155:60434 192.168.0.35:3260
> ESTABLISHED 5658/iscsid
> <snip>
>
> I would want to associate that with a specific connection so I can analyze
> tcpdump output for just that one connection that is seemingly
> underperforming. The host has dozens of active connections and only this
> one is causing a problem. Without being able to identify the source port,
> it is difficult to determine which stream to follow.
>
> Thanks,
> Jeff
>
> On Tuesday, August 28, 2012 5:02:41 PM UTC-7, Mike Christie wrote:
>>
>>
>> On Aug 28, 2012, at 5:39 PM, Jeffrey Caughel <jcau...@gmail.com<javascript:>>

[abhinav.s...@gmail.com]

Hi Mike,

I am trying to extract the same information i.e. local IP and port combination corresponding to a iscsi connection. Do you know how to extract this information? iscsiadm -m session still only prints the local IP. Any help would appreciated.

Thanks.
Abhinav

[Michael Christie]

Hey,

I made patches for this a while back. I am in the middle of finishing up some work release stuff then changing jobs. I should be able to get back to this next week. 

--
You received this message because you are subscribed to the Google Groups "open-iscsi" group.
To unsubscribe from this group and stop receiving emails from it, send an email to open-iscsi+...@googlegroups.com.
To post to this group, send email to open-...@googlegroups.com.
Visit this group at http://groups.google.com/group/open-iscsi.
For more options, visit https://groups.google.com/d/optout.

[abhinav.s...@gmail.com]

Mike, thanks for the reply. Look forward to hearing from you soon regarding the patch.

[abhinav.s...@gmail.com]

Hi Mike, would you be able to share your patch with me? Thanks.

[Mike Christie]

There are 2 patches attached.

1. iscsi-tcp-export-local-port.patch.

This is required. Apply this to your kernel. When you login you will see

/sys/class/iscsi_connection/connection1:0/local_port

cat /sys/class/iscsi_connection/connection1:0/local_port
57568

This would match what you see in netstat:

netstat -anpt | grep iscsid
tcp 0 0 20.15.0.24:57568 20.15.0.32:3260
ESTABLISHED 9261/iscsid

This patch should hopefully get into 3.18.

2. iscsiadm-print-local-port.patch

This is optional. It just has iscsiadm print the local port info. If you
do not have it, you can get it from sysfs like above. This patch
requires that the kernel patch be applied.

On 08/20/2014 09:02 AM, abhinav.s...@gmail.com wrote:
>
> Hi Mike, would you be able to share your patch with me? Thanks.
>
> On Monday, August 11, 2014 11:31:57 PM UTC-4, Mike Christie wrote:
>
> Hey,
>
> I made patches for this a while back. I am in the middle of
> finishing up some work release stuff then changing jobs. I should be
> able to get back to this next week.
>

> On Aug 6, 2014, at 4:20 PM, abhinav.s...@gmail.com <javascript:> wrote:
>
>>
>> Hi Mike,
>>
>> I am trying to extract the same information i.e. local IP and port
>> combination corresponding to a iscsi connection. Do you know how
>> to extract this information? iscsiadm -m session still only prints
>> the local IP. Any help would appreciated.
>>
>> Thanks.
>> Abhinav
>>
>> On Thursday, August 30, 2012 3:58:05 PM UTC-4, Mike Christie wrote:
>>
>> Ok. Let me try to get to this over the weekend.
>>
>> On 08/28/2012 07:29 PM, Jeffrey Caughel wrote:
>> > That is exactly what I am looking for... peresently I can
>> see something
>> > like this:
>> >
>> > # netstat -anpt
>> > <snip>
>> > tcp 0 48 192.168.0.155:60480

>> <http://192.168.0.155:60480/> 192.168.0.35:3260
>> <http://192.168.0.35:3260/>

>> > ESTABLISHED 5658/iscsid
>> > tcp 0 0 192.168.0.155:60452

>> <http://192.168.0.155:60452/> 192.168.0.35:3260
>> <http://192.168.0.35:3260/>

>> > ESTABLISHED 5658/iscsid
>> > tcp 0 48 192.168.0.155:60448

>> <http://192.168.0.155:60448/> 192.168.0.35:3260
>> <http://192.168.0.35:3260/>

>> > ESTABLISHED 5658/iscsid
>> > tcp 0 0 192.168.0.155:60460

>> <http://192.168.0.155:60460/> 192.168.0.35:3260
>> <http://192.168.0.35:3260/>

>> > ESTABLISHED 5658/iscsid
>> > tcp 0 0 192.168.0.155:60458

>> <http://192.168.0.155:60458/> 192.168.0.35:3260
>> <http://192.168.0.35:3260/>

>> > ESTABLISHED 5658/iscsid
>> > tcp 0 0 192.168.0.155:60466

>> <http://192.168.0.155:60466/> 192.168.0.35:3260
>> <http://192.168.0.35:3260/>

>> > ESTABLISHED 5658/iscsid
>> > tcp 0 0 192.168.0.155:60420

>> <http://192.168.0.155:60420/> 192.168.0.35:3260
>> <http://192.168.0.35:3260/>

>> > ESTABLISHED 5658/iscsid
>> > tcp 0 0 192.168.0.155:60422

>> <http://192.168.0.155:60422/> 192.168.0.35:3260
>> <http://192.168.0.35:3260/>

>> > ESTABLISHED 5658/iscsid
>> > tcp 0 0 192.168.0.155:60434

>> <http://192.168.0.155:60434/> 192.168.0.35:3260
>> <http://192.168.0.35:3260/>

>> send an email to open-iscsi+...@googlegroups.com <javascript:>.

>> To post to this group, send email to open-...@googlegroups.com

>> <javascript:>.

>> Visit this group at http://groups.google.com/group/open-iscsi

>> <http://groups.google.com/group/open-iscsi>.

>> For more options, visit https://groups.google.com/d/optout

>> <https://groups.google.com/d/optout>.

>
> --
> You received this message because you are subscribed to the Google
> Groups "open-iscsi" group.
> To unsubscribe from this group and stop receiving emails from it, send
> an email to open-iscsi+...@googlegroups.com

> <mailto:open-iscsi+...@googlegroups.com>.

> To post to this group, send email to open-...@googlegroups.com

> <mailto:open-...@googlegroups.com>.

[abhinav.s...@gmail.com]

Thanks Mike. I will use them and let you know.

> <mailto:open-iscsi+unsub...@googlegroups.com>.