01-07-2004 02:21 PM
I have 2 CSS 11052 making server load balancing at layer 3 (with four web servers). I have a VIP addr to talk with clients and 2 FW1 "next generation) in Win200 servers between the CSS and the clients. My clients have some problems in the the establish of the session (http or https). When the session are established they work well.
With a sniffer near the client i saw the client send 2, 3, or more "syn" till they have the "synack" and the session are established.
With a sniffer between the CSS and the web servers i saw the "syn's" that are sent by the client and i saw "synack" for every "syn" till the session are established.
Where are the "synack" sent by the web servers?
Any idea?
01-08-2004 03:44 AM
are the servers directly connected to the CSS ?
Is the CSS the default gateway for the servers ?
Can the server bypass the CSS ?
What you have to make sure is that the server response goes through the CSS.
Check the destination mac address in the syn/ack and make sure this is the CSS.
Do you have ACL on the CSS ?
If so try to disable them.
Can we have the config of the CSS ? content rules and services.
Are the services seen as alive ?
Can you ping the VIP ?
Any transition with the service ?
As you can see there are many possibilities.
I would suggest to start by sending the config and a 'sho summary' and 'sho serv summary'.
Also make sure traffic goes back to the CSS.
Gilles.
01-26-2004 12:09 PM
I am curious as to why you asked if ACL was enabled.
I have a similar problem where I have web clients that access the Internet via a 11050. The client sends a SYN, the web server responds with SYNACK, the client then sends ACK. However, a sniffer on the Internet side of the CSS shows the CSS dropped the final ACK.
If I disable ACLs, the problem disappears.
Is there any relation?
01-08-2004 04:48 AM
The servers are connected to a 3524XL switch.
The CSS is the default gateway to the servers.
The server can bypass the CSS if we change the gateway, because the firewalls are in the same network.
I don´t have any ACL in the CSS
The services are alive.
I can ping the VIP.
CONFIG:
CSS-1A# version
Version: ap0500033 (5.00 Build 33)
Flash (Locked): 5.00 Build 33
Flash (Operational): 5.00 Build 33
Type: PRIMARY
Licensed Cmd Set(s): Standard Feature Set
SSH Server
CSS-1A# sh boot
!************************ BOOT CONFIG ************************
ip address 192.168.7.242
subnet mask 255.255.255.0
primary boot-file ap0500033
primary boot-type boot-via-disk
CSS-1A# sh run
!Generated on 02/26/2003 19:32:32
!Active version: ap0500033
configure
!*************************** GLOBAL ***************************
ip redundancy
no restrict web-mgmt
no restrict xml
restrict ftp
restrict telnet
restrict user-database
restrict snmp
app session 192.168.100.2
app
ip route 0.0.0.0 0.0.0.0 192.168.1.254 1
!************************* INTERFACE *************************
interface e1
phy 100Mbits-FD
bridge vlan 3
description "HeartBeat"
interface e2
phy 100Mbits-FD
bridge vlan 2
redundancy-phy
description "UP-Link to FW01N1 via Switch-3A"
interface e3
phy 100Mbits-FD
bridge vlan 2
interface e4
phy 100Mbits-FD
bridge vlan 2
interface e5
phy 100Mbits-FD
bridge vlan 2
interface e6
phy 100Mbits-FD
bridge vlan 2
interface e7
phy 100Mbits-FD
bridge vlan 2
interface e8
phy 100Mbits-FD
bridge vlan 4
!************************** CIRCUIT **************************
circuit VLAN3
ip address 192.168.100.1 255.255.255.0
redundancy-protocol
circuit VLAN2
redundancy
ip address 192.168.1.250 255.255.255.0
circuit VLAN4
ip address 10.6.1.60 255.255.255.128
!************************** SERVICE **************************
service WEB01_HTTP
ip address 192.168.1.31
keepalive type tcp
keepalive port 80
keepalive frequency 15
keepalive maxfailure 2
active
service WEB01_HTTP&HTTPS
ip address 192.168.1.31
keepalive frequency 15
keepalive maxfailure 2
active
service WEB01_HTTPHEADwebinfo
ip address 192.168.1.31
keepalive type script ap-kal-httplist "192.168.1.31 /webinfo.asp"
keepalive frequency 15
keepalive maxfailure 2
active
service WEB01_HTTPS
ip address 192.168.1.31
keepalive type tcp
keepalive port 443
keepalive frequency 15
keepalive maxfailure 2
active
service WEB02_HTTP
ip address 192.168.1.32
keepalive type tcp
keepalive port 80
keepalive frequency 15
keepalive maxfailure 2
active
service WEB02_HTTP&HTTPS
ip address 192.168.1.32
keepalive frequency 15
keepalive maxfailure 2
active
service WEB02_HTTPHEADwebinfo
ip address 192.168.1.32
keepalive type script ap-kal-httplist "192.168.1.32 /webinfo.asp"
keepalive frequency 15
keepalive maxfailure 2
active
service WEB02_HTTPS
ip address 192.168.1.32
keepalive type tcp
keepalive port 443
keepalive frequency 15
keepalive maxfailure 2
active
service WEB03_HTTP
ip address 192.168.1.33
keepalive type tcp
keepalive port 80
keepalive frequency 15
keepalive maxfailure 2
active
service WEB03_HTTP&HTTPS
ip address 192.168.1.33
keepalive frequency 15
keepalive maxfailure 2
active
service WEB03_HTTPHEADwebinfo
ip address 192.168.1.33
keepalive type script ap-kal-httplist "192.168.1.33 /webinfo.asp"
keepalive frequency 15
keepalive maxfailure 2
active
service WEB03_HTTPS
ip address 192.168.1.33
keepalive type tcp
keepalive port 443
keepalive frequency 15
keepalive maxfailure 2
active
service WEB04_HTTP
ip address 192.168.1.34
keepalive type tcp
keepalive port 80
keepalive frequency 15
keepalive maxfailure 2
active
service WEB04_HTTP&HTTPS
ip address 192.168.1.34
keepalive frequency 15
keepalive maxfailure 2
keepalive type script ap-kal-dcheck "192.168.1.34"
active
service WEB04_HTTPHEADwebinfo
ip address 192.168.1.34
keepalive type script ap-kal-httplist "192.168.1.34 /webinfo.asp"
keepalive frequency 15
keepalive maxfailure 2
active
service WEB04_HTTPS
ip address 192.168.1.34
keepalive type tcp
keepalive port 443
keepalive frequency 15
keepalive maxfailure 2
active
!*************************** OWNER ***************************
owner www.cidadebcp.pt
content Rule_HTTP
vip address 192.168.1.100
protocol tcp
port 80
advanced-balance sticky-srcip
add service WEB01_HTTP&HTTPS
add service WEB02_HTTP&HTTPS
add service WEB03_HTTP&HTTPS
add service WEB04_HTTP&HTTPS
active
content Rule_HTTPS
vip address 192.168.1.100
protocol tcp
port 443
advanced-balance sticky-srcip
add service WEB02_HTTP&HTTPS
add service WEB01_HTTP&HTTPS
add service WEB03_HTTP&HTTPS
add service WEB04_HTTP&HTTPS
active
SHOW SUMMARY
CSS-1A# sh summ
Global Bypass Counters:
No Rule Bypass Count: 1406999
Acl Bypass Count: 0
Owner Content Rules State Services Service Hits
www.?????????.pt Rule_HTTP Active WEB01_HTTP&HTTPS 23851961
WEB02_HTTP&HTTPS 23432601
WEB03_HTTP&HTTPS 25224983
WEB04_HTTP&HTTPS 20882126
Rule_HTTPS Active WEB01_HTTP&HTTPS 34624556
WEB02_HTTP&HTTPS 32311666
WEB03_HTTP&HTTPS 33279661
WEB04_HTTP&HTTPS 30738365
SHOW SERV SUMMARY
CSS-1A# show serv summ
Service not found
I hope that this information is enough to you.
If you want i can send you the same information by mail. Tell me if necessary.
01-09-2004 02:03 AM
could you send me a topology map and the sniffer traces by email - gdufour@cisco.com
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