LVS
lvs-users
Google
 
Web LinuxVirtualServer.org

Re: port unreachable

To: "LinuxVirtualServer.org users mailing list." <lvs-users@xxxxxxxxxxxxxxxxxxxxxx>
Subject: Re: port unreachable
From: "Martijn Grendelman" <martijn@xxxxxxxxxxxxxx>
Date: Mon, 8 Mar 2004 14:33:07 +0100
> I think it has something  todo with scheduler sh, I see that you use
> also sh. I have changed from sh to rr a week ago and now I have no
> problems any more.
>
> Mmm, a litte bug in source hashing???

I was also thinking in that direction. I haven't seen the problem with
only one real server. But that brings up another problem. I use source
hashing to make sure http sessions work, and I have no alternative for
that (persistence in LVS doesn't do it). Session data is not shared
between servers and I don't see an easy way of doing that. But that's a
different discussion ;-) I hope a bug in LVS will be found and fixed soon!

Regards,
Martijn.



>
> -----Original Message-----
> From: Martijn Grendelman [mailto:martijn@xxxxxxxxxxxxxx]
> Sent: maandag 8 maart 2004 12:56
> To: lvs-users@xxxxxxxxxxxxxxxxxxxxxx
> Subject: Re: port unreachable
>
>
> Hi,
>
>> I have the following problem, I have a loadbalancer to loadbalance
>> https/http, pop and smtp request. Al are working fine except for
>> https. I get some times a connection refused. If I look with tcpdump
>> I
>
>> get a "tcp port https unreachable". But the real servers are ok, I
>> test them also directly no problem with that. But via the
>> loadbalancer
>
>> I get sometimes the port unreachable problem. At that time both the
>> realservers are in the loadbalancer.
>
> I've got the same problem, but also with http. I use LVS-DR with one
> of the real servers on the director:
>
> IP Virtual Server version 1.0.10 (size=4096)
> Prot LocalAddress:Port Scheduler Flags
>   -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
> TCP  212.204.230.98:80 sh
>   -> 212.204.230.91:80            Route   1      3          0
>   -> 212.204.230.96:80            Local   1      0          0
>
> Both real servers work fine, and most of the time, the virtual server
> also works. However sometimes, clients get "connection refused".
> After a few minutes, everything's fine again.
>
> A tcpdump on the client shows "bad tcp cksum". Unfortunately I don't
> know what that means.
>
> 11:02:06.112745 IP (tos 0x0, ttl  64, id 35405, offset 0, flags [DF],
> length: 60) 10.60.0.20.50259 > 212.204.230.98.http: S [bad tcp cksum
> c5ad (->95f7)!] 4101824739:4101824739(0) win 65535 <mss
> 1460,nop,wscale 0,nop,nop,timestamp 918167251 0>
>
> The load balancer returns ICMP port unreachable messages to the
> client:
>
> 12:32:55.431896 212.204.230.98 > hq.appoint.nl: icmp: 212.204.230.98
> tcp port www unreachable for hq.appoint.nl.52752 >
> 212.204.230.98.www: S 2831096624:2831096624(0) win 65535 <mss
> 1460,nop,wscale 0,nop,nop,timestamp[|tcp]> (DF) (ttl 58, id 20064,
> len 60) [tos 0xc0] (ttl 64, id 23682, len 88)
>
> I hope someone can help. At this point, I don't consider the LVS ready
> for production :-(
>
> Best regards,
> Martijn.
>
> _______________________________________________
> LinuxVirtualServer.org mailing list - lvs-users@xxxxxxxxxxxxxxxxxxxxxx
> Send requests to lvs-users-request@xxxxxxxxxxxxxxxxxxxxxx
> or go to http://www.in-addr.de/mailman/listinfo/lvs-users
> _______________________________________________
> LinuxVirtualServer.org mailing list - lvs-users@xxxxxxxxxxxxxxxxxxxxxx
> Send requests to lvs-users-request@xxxxxxxxxxxxxxxxxxxxxx
> or go to http://www.in-addr.de/mailman/listinfo/lvs-users

<Prev in Thread] Current Thread [Next in Thread>