LVS
lvs-users
Google
 
Web LinuxVirtualServer.org

Re: [lvs-users] keepalived: SSH getting "No route to host"

To: "LinuxVirtualServer.org users mailing list." <lvs-users@xxxxxxxxxxxxxxxxxxxxxx>
Subject: Re: [lvs-users] keepalived: SSH getting "No route to host"
From: Gerry Reno <greno@xxxxxxxxxxx>
Date: Thu, 20 Sep 2007 00:58:56 -0400
Gerry Reno wrote:
> I have setup a stanza in keepalived.conf for SSH to use an alternate 
> port.  But whenever I try to ssh into the VIP on the alternate port I 
> get a "No route to host".  It looks like it gets to the director but it 
> never gets to the real server.  I see an immediate inactive connection 
> in IPVS.  All firewalls on both directors and real servers are down.  
> keepalived is 1.1.13.  All the other IPVS traffic is behaving correctly, 
> 80, 8080, 443.
>
> ????
>
> Gerry
>
>
> =====================================================
> On a non-director machine:
> # ssh -p 33322 -v root@xxxxxxxxxxxxx
> OpenSSH_4.5p1, OpenSSL 0.9.8b 04 May 2006
> debug1: Reading configuration data /etc/ssh/ssh_config
> debug1: Applying options for *
> debug1: Connecting to 192.168.1.240 [192.168.1.240] port 33322.
> debug1: connect to address 192.168.1.240 port 33322: No route to host
> ssh: connect to host 192.168.1.240 port 33322: No route to host
>
>
> On director:
> # ipvsadm -ln
> IP Virtual Server version 1.2.1 (size=4096)
> Prot LocalAddress:Port Scheduler Flags
>   -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
> TCP  192.168.1.240:443 rr persistent 600
>   -> 192.168.1.201:443            Route   1      0          0        
>   -> 192.168.1.200:443            Route   1      0          0        
> TCP  192.168.1.240:33322 rr persistent 600
>   -> 192.168.1.26:22              Route   1      0          0        
>   -> 192.168.1.25:22              Route   1      0          1        
>
>
> keepalived.conf:
> ...
> virtual_server 192.168.1.240 33322 {
>         delay_loop 5
>         lb_algo rr
>         lb_kind DR
>         persistence_timeout 600
>         protocol TCP
>
>         real_server 192.168.1.25 22 { 
>                 weight 1
>                 inhibit_on_failure
>                 TCP_CHECK {
>                         connect_port 22
>                         connect_timeout 3
>                         nb_get_retry 3
>                         delay_before_retry 1
>                 }
>         }
>         real_server 192.168.1.26 22 { 
>                 weight 1
>                 inhibit_on_failure
>                 TCP_CHECK {
>                         connect_port 22
>                         connect_timeout 3
>                         nb_get_retry 3
>                         delay_before_retry 1
>                 }
>         }
> }
> ...
>
> master director:
> # ip addr show
> 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue
>     link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
>     inet 127.0.0.1/8 scope host lo
>     inet6 ::1/128 scope host
>        valid_lft forever preferred_lft forever
> 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast 
> qlen 1000
>     link/ether 00:0c:29:a7:c7:33 brd ff:ff:ff:ff:ff:ff
>     inet 192.168.1.150/24 brd 192.168.1.255 scope global eth0
>     inet 192.168.1.240/24 scope global secondary eth0
>     inet6 fe80::20c:29ff:fea7:c733/64 scope link
>        valid_lft forever preferred_lft forever
>
> backup director:
> # ip addr show
> 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue
>     link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
>     inet 127.0.0.1/8 scope host lo
>     inet 192.168.1.240/32 scope host lo
>     inet6 ::1/128 scope host
>        valid_lft forever preferred_lft forever
> 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast 
> qlen 1000
>     link/ether 00:0c:29:54:ef:09 brd ff:ff:ff:ff:ff:ff
>     inet 192.168.1.151/24 brd 192.168.1.255 scope global eth0
>     inet6 fe80::20c:29ff:fe54:ef09/64 scope link
>        valid_lft forever preferred_lft forever
>
> realservers:
> 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue
>     link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
>     inet 127.0.0.1/8 scope host lo
>     inet6 ::1/128 scope host
>        valid_lft forever preferred_lft forever
> 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast 
> qlen 1000
>     link/ether 00:18:f8:0b:55:54 brd ff:ff:ff:ff:ff:ff
>     inet 192.168.1.25/24 brd 192.168.1.255 scope global eth0
>     inet6 fe80::218:f8ff:fe0b:5554/64 scope link
>        valid_lft forever preferred_lft forever
>
>   
I'm also seeing a lot of these in /var/log/secure:
Sep 19 23:22:12 grp-01-20-01 sshd[22408]: Did not receive identification 
string from 192.168.1.150
Sep 19 23:39:42 grp-01-20-01 sshd[22868]: Did not receive identification 
string from 192.168.1.150
Sep 19 23:39:47 grp-01-20-01 sshd[22871]: Did not receive identification 
string from 192.168.1.150

which I'm assuming is from TCP_CHECK




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