Search Results

Search found 8979 results on 360 pages for 'dynamic routing'.

Page 61/360 | < Previous Page | 57 58 59 60 61 62 63 64 65 66 67 68 | Next Page >

Hubs/switches taking out switches?

- by Bart Silverstrim

Here's the issue...we have a network with a lot of Cisco switches. Someone plugged in a hub on the network, and then we started seeing "weird" behavior; errors in communication between clients and servers, or network timeouts, dropping network connections, etc. It seemed that somehow that hub (or SOHO switch) was particularly freaking out our Cisco 3700 series switches. Disconnect that hub or netgear-type SOHO switch and things settled down again. We're in the process of trying to get a centralized logging server for SNMP and management, etc., to see if we can trap errors or narrow down when someone does this sort of thing without our knowledge because things seem to work, for the most part, without issue, we just get freaky oddball incidents on particular switches that don't seem to have any explanation until we find out someone decided to take matters into their own hands to expand available ports in their room. Without getting into procedure changes or locking down ports or "in our organization they'd be fired" answers, can someone explain why adding a small switch or hub, not necessarily a SOHO router (even a dumb hub apparently caused the 3700's to freak out) sending DHCP request out, will cause issues? The boss said it's because the Cisco's are getting confused because that rogue hub/switch is bridging multiple MAC's/IP's into one port on the Cisco switches and they just choke on that, but I thought their routing tables should be able to handle multiple machines coming into the port. Anyone see that behavior before and have a clearer explanation of what's happening? I'd like to know for future troubleshooting and better understanding that just waving my hand and saying "you just can't".

Read the article
Route all traffic via OpenVPN client

- by Ilya

I've got OpenVPN client running on 192.168.0.3. What I'd like to do is route all the traffic from the second computer with 192.168.0.100 via OpenVPN client that's running on the first computer. My router ip is 192.168.0.1 Network topology: Windows computer with OpenVPN client: 192.168.0.3 Windows computer whose traffic has to be rerouted: 192.168.0.100 Router: 192.168.0.1 I want it to work in the following way: 192.168.0.100 computer => 192.168.0.3 computer => OpenVPN => 192.168.0.1 How can I achieve that by only modifying windows' routing table? I've tried entering the following into windows shell(on computer without VPN), which didn't work (it just dropped my internet connection): route delete 0.0.0.0 mask 255.255.255.255 192.168.0.1 route add 0.0.0.0 mask 255.255.255.255 192.168.0.3 Should I also setup the computer that has OpenVPN client running? Does it have anything to do with windows tcp forwarding? Thanks!

Read the article
Two DHCP servers on the same network

- by CesarGon

We are setting up a routing link between the Windows Server 2008 networks of two different buildings in my organisation. Each network uses a different IP addressing scheme (one uses public addresses, the other one uses private), but the goal is having a single Windows Server domain across the gap between the buildings. The link is provided by a 100-Mbps point-to-point line. I have always understood that you should not have more than one DHCP server on a network. However, we are planning to put a domain controller on each building, and each domain controller will be a DNS server and a DHCP server as well. The intention is that a machine booting up in building A gets its IP address from the DHCP server closer to it, in building A, while a machine booting up in building B gets an address from the DHCP server in building B. Since the two buildings will be linked and the network will be only one, will this work? How can I avoid that a machine booting up in building A gets an address from the DHCP server in building B (or vice versa)? Thanks.

Read the article
Two DHCP servers on the same network

- by CesarGon

We are setting up a routing link between the Windows Server 2008 networks of two different buildings in my organisation. Each network uses a different IP addressing scheme (one uses public addresses, the other one uses private), but the goal is having a single Windows Server domain across the gap between the buildings. The link is provided by a 100-Mbps point-to-point line. I have always understood that you should not have more than one DHCP server on a network. However, we are planning to put a domain controller on each building, and each domain controller will be a DNS server and a DHCP server as well. The intention is that a machine booting up in building A gets its IP address from the DHCP server closer to it, in building A, while a machine booting up in building B gets an address from the DHCP server in building B. Since the two buildings will be linked and the network will be only one, will this work? How can I avoid that a machine booting up in building A gets an address from the DHCP server in building B (or vice versa)? Thanks.

Read the article
Why can't I route to some sites from my MacBook Pro that I can see from my iPad? [closed]

- by Robert Atkins

I am on M1 Cable (residential) broadband in Singapore. I have an intermittent problem routing to some sites from my MacBook Pro—often Google-related sites (arduino.googlecode.com and ajax.googleapis.com right now, but sometimes even gmail.com.) This prevents StackExchange chat from working, for instance. Funny thing is, my iPad can route to those sites and they're on the same wireless network! I can ping the sites, but not traceroute to them which I find odd. That I can get through via the iPad implies the problem is with the MBP. In any case, calling M1 support is... not helpful. I get the same behaviour when I bypass the Airport Express entirely and plug the MBP directly into the cable modem. Can anybody explain a) how this is even possible and b) how to fix it? mella:~ ratkins$ ping ajax.googleapis.com PING googleapis.l.google.com (209.85.132.95): 56 data bytes 64 bytes from 209.85.132.95: icmp_seq=0 ttl=50 time=11.488 ms 64 bytes from 209.85.132.95: icmp_seq=1 ttl=53 time=13.012 ms 64 bytes from 209.85.132.95: icmp_seq=2 ttl=53 time=13.048 ms ^C --- googleapis.l.google.com ping statistics --- 3 packets transmitted, 3 packets received, 0.0% packet loss round-trip min/avg/max/stddev = 11.488/12.516/13.048/0.727 ms mella:~ ratkins$ traceroute ajax.googleapis.com traceroute to googleapis.l.google.com (209.85.132.95), 64 hops max, 52 byte packets traceroute: sendto: No route to host 1 traceroute: wrote googleapis.l.google.com 52 chars, ret=-1 *traceroute: sendto: No route to host traceroute: wrote googleapis.l.google.com 52 chars, ret=-1 ^C mella:~ ratkins$ The traceroute from the iPad goes (and I'm copying this by hand): 10.0.1.1 119.56.34.1 172.20.8.222 172.31.253.11 202.65.245.1 202.65.245.142 209.85.243.156 72.14.233.145 209.85.132.82 From the MBP, I can't traceroute to any of the IPs from 172.20.8.222 onwards. [For extra flavour, not being able to access the above appears to stop me logging in to Server Fault via OpenID and formatting the above traceroutes correctly. Anyone with sufficient rep here to do so, I'd be much obliged.]

Read the article
Private staff network within public network

- by pianohacker

I'm the sysadmin at a small public library. Since I got here a few years ago, I've been trying to set up the network in a secure and simple way. Security is a little tricky; the staff and patron networks need to be separated, for security reasons. Even if I further isolated the public wireless, I'd still rather not trust the security of our public computers. However, the two networks also need to communicate; even if I set up enough VMs so they didn't share any servers, they need to use the same two printers at the very least. Currently, I'm solving this with some jerry-rigged commodity equipment. The patron network, linked together by switches, has a Windows server connected to it for DNS and DHCP and a DSL modem for a gateway. Also on the patron network is the WAN side of a Linksys router. This router is the "top" of the staff network, and has the same Windows server connected on a different port, providing DNS and DHCP, and another, faster DSL modem (separate connections are very useful, especially as we heavily depend on some cloud-hosted software). tl;dr: We have a public network, and a NATed staff network within it. My question is; is this really the best way to do this? The right equipment would likely make my job easier, but anything with more than four ports and even rudimentary management quickly becomes a heavy hit on our budget. (My original question was about an ungodly frustrating DHCP routing issue, but I thought I'd ask whether my network was broken rather than asking about the DHCP problem and being told my network was broken.)

Read the article
Home network with two isolated separate subnets, running on cablemodem/router and WRT-router.

- by Johan Allgoth

I have a new connection with a nice new router/cable-modem. I'd like to setup it up optimally and needs some pointers. I am a complete n00b when it comes to routing. I want to end up with two separate subnets, 10.1.2.0/24 and 192.168.1.0/24 each available on their own wireless channel/SSID. Both firewalled. I want my wired computers on the gigabit switch, optimally with public ips. I want to be able to reach 192.168.1.0/24 from 10.1.2.0/24, but not vice versa. Everyone should have internet access. Hardware and capabilities: Netgear CG3100. Handles cable connection. Gigabit switch. 802.11n. Can do DHCP, firewall, NAT etc. Can choose subnet. Can turn of NAT and if so hand out up to 4 public ips. Somewhat challenged when it comes to configuration. WRT-router. Runs DD/Open-WRT very stable. 100 Mbit switch. 802.11.g Can do DHCP, firewall, NAT etc. Can choose subnet. Highly configurable. I hope to be able to keep 10.1.2.0/24 on the CG3100, for speed reasons and 192.168.0.0/24 on the WRT-router for quota and user control reasons. On my 10.1.2.0/24 network I plan on running servers for various services. Should I turn of NAT on the WRT-router? Or on the cable modem? Activate what in that case? Is double NAT always f-ed up?

Read the article
VLAN ACLs and when to go Layer 3

- by wuckachucka

I want to: a) segment several departments into VLANs with the hopes of restricting access between them completely (Sales never needs to talk to Support's workstations or printers and vice-versa) or b) certain IP addresses and TCP/UDP ports across VLANS -- i.e. permitting the Sales VLAN to access the CRM Web Server in the Server VLAN on port 443 only. Port-wise, I'll need a 48-port switch and another 24-port switch to go with the two existing 24-port Layer 2 switches (Linksys); I'm looking at going with D-Links or HP Procurves as Cisco is out of our price range. Question #1: From what I understand (and please correct me if I'm wrong), if the Servers (VLAN10) and Sales (VLAN20) are all on the same 48-port switch (or two stacked 24-port switches), afaik, the switch "knows" what VLANs and ports each device belongs to and will switch packets between them; I can also apply ACLs to restrict access between VLANs at this point. Is this correct? Question #2: Now lets say that Support (VLAN30) is on a different switch (one of the Linksys) switches. I'm assuming I'll need to trunk (tag) switch #2's VLANs across to switch #1, so switch #1 sees switch #2's VLAN30 (and vice-versa). Once Switch #1 can "see" VLAN30, I'm assuming I can then apply ACLs as stated in Question #1. Is this correct? Question #3: Once Switch #1 can see all the VLANs, can I achieve the seemingly "Layer 3" ACL filtering of restricting access to Server VLAN on only certain TCP/UDP ports and IP addresses (say, only permitting 3389 to the Terminal Server, 192.168.10.4/32). I say "seemingly" because some of the Layer 2 switches mention the ability to restrict ports and IP addresses through the ACLs; I (perhaps mistakenly) thought that in order to have Layer 3 ACLs (packet filtering), I'd need to have at least one Layer 3 switch acting as a core router. If my assumptions are incorrect, at which point do you need a Layer 3 switch for inter-VLAN routing vs. inter-VLAN switching? Is it generally only when you need that higher-level packet filtering ability between your departments?

Read the article
How is route automatic metric calculated on Windows 7?

- by e-t172

KB299540 explains how Windows XP automatically assign metrics to IP routes: The following table outlines the criteria that is used to assign metrics for routes that are bound to network interfaces of various speeds. Greater than 200 Mb: 10 Greater than 20 Mb, and less than or equal to 200 Mb: 20 Greater than 4 Mb, and less than or equal to 20 Mb: 30 Greater than 500 kilobits (Kb), and less than or equal to 4 Mb: 40 Less than or equal to 500 Kb: 50 However, they seem to have changed their algorithm in Windows 7, as my routing table looks like this: IPv4 Route Table =========================================================================== Active Routes: Network Destination Netmask Gateway Interface Metric 0.0.0.0 0.0.0.0 192.168.0.1 192.168.0.3 10 0.0.0.0 0.0.0.0 10.202.254.254 10.202.1.2 286 10.202.0.0 255.255.0.0 On-link 10.202.1.2 286 10.202.1.2 255.255.255.255 On-link 10.202.1.2 286 10.202.255.255 255.255.255.255 On-link 10.202.1.2 286 127.0.0.0 255.0.0.0 On-link 127.0.0.1 306 127.0.0.1 255.255.255.255 On-link 127.0.0.1 306 127.255.255.255 255.255.255.255 On-link 127.0.0.1 306 192.168.0.0 255.255.255.0 On-link 192.168.0.3 266 192.168.0.3 255.255.255.255 On-link 192.168.0.3 266 192.168.0.255 255.255.255.255 On-link 192.168.0.3 266 224.0.0.0 240.0.0.0 On-link 127.0.0.1 306 224.0.0.0 240.0.0.0 On-link 192.168.0.3 266 224.0.0.0 240.0.0.0 On-link 10.202.1.2 286 255.255.255.255 255.255.255.255 On-link 10.202.1.2 40 =========================================================================== The only "correct" metric is the first one (Gigabit connection = 10). However, other routes using the Gigabit connection have metric = 266, my VPN has metric = 286, and loopback is 306 (?!). Any idea what's going on?

Read the article
Route all wlan0 traffic over tun0

- by Tuinslak

I'm looking for a way to route all wlan0 traffic (tcp and udp) over tun0 (openvpn). However, all other traffic originating from the device itself should not be routed through tun0. I'm guessing this could be realized using iptables or route, but none of my options seem to work. # route add -net 0.0.0.0 gw 172.27.0.1 dev wlan0 SIOCADDRT: No such process Info: This is because the VPN server is not redundant, and wlan users are not really important. However, all services running on the device are fairly important and having a VPN virtual machine with no SLA on it is just a bad idea. Trying to minimize the odds of something going wrong. So setting the VPN server as default gateway is not really an option. I also want all wlan0 user to use the VPN server's IP address as external IP. Edit with the script provided: root@ft-genesi-xxx ~ # route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 172.27.0.17 0.0.0.0 255.255.255.255 UH 0 0 0 tun0 192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 10.13.37.0 0.0.0.0 255.255.255.0 U 0 0 0 wlan0 172.27.0.0 172.27.0.17 255.255.192.0 UG 0 0 0 tun0 0.0.0.0 192.168.1.1 0.0.0.0 UG 0 0 0 eth0 root@ft-genesi-xxx ~ # ./test.sh RTNETLINK answers: No such process root@ft-genesi-xxx ~ # cat test.sh #!/bin/sh IP=/sbin/ip # replace with the range of your wlan network, or use fwmark instead ${IP} rule add from 10.13.37.0/24 table from-wlan ${IP} route add default dev tun0 via 127.72.0.1 table from-wlan ${IP} route add 10.13.37.0/24 dev wlan0 table from-wlan

Read the article
Route specific network traffic through vpn in virtualbox guest

- by Sander

I am running OSX with a windows server 2008 guest in Virtualbox. My goal is to route some of the network traffic in the host through the server guest. This is because the win2008 server has a VPN connection to my workplace using a Smartcard solution which can not operate on OSX. My current set-up is like this: OSX (Host): connected to the internet via en01 Win2008 (Guest): connected to the internet using NAT (lan1 in guest) has a SSTP VPN connection to my workplace is connected to the guest using an Host Only Adapter vboxnet0 (LAN2 in guest) The important part is about the host (OSX). Primarily I want all network traffic to just go through en01. However, all traffic which can only be accessed through the VPN must go through the guest and through the VPN. I have one specific FQDN which can only be accessed through the VPN (say corp.mycompany.com). I do not know much about networking. I thought I would be able to get it to work by bridging together LAN2 and LAN1 but this didn't seem to work this: http://archives.aidanfindlater.com/blog/2010/02/03/use-vpn-for-specific-sites-on-mac-os-x/ using a loopback adapter on WinXP (when I did not have win2008 yet, but this doesn't work because I can't create a PPTP connection) And I've also read about Routing and Remote Access but I have no idea on how to use this. Can someone help me in the right direction?

Read the article
Intermittently uncommunicative subnets

- by mhd

Last week proved me a veritable Cassandra: I've always said that it's a bad idea to have only one firewall/router, without a backup or failover. And thus our Cisco PIX went haywire, refusing to route properly. And of course, the only one available here on short notice is me, and while I'm quite grounded in Linux, I'm really a developer not a sysadmin (the fact that this hit me on sysadmin appreciation day is a bit ironic). Anyway, this weekend I tried to hack up a temporary solution: I used an old server with enough NICs (two built-in, four on a card) to serve as a gateway and firewall. Due to some problems with the raid controller, I got only two router distros running, and between Untangle and Ebox I decided for the latter. Now everything is quite okay. I've got all the different subnets we've got here (all with separate switches) talking to each other and even to the internet (Cisco 2800 router, T1 lines). But from time to time (20-60 minute intervals), I get a total routing failure. Our main, office subnet can't talk to our server subnet and can't connect to the internet. This is not the end of a gradual slowdown, either everything's working perfectly or I get a total lack of communication for about two minutes each time. Now I'm a bit at wits end what to check. At least with the default EBox setup, nothing in /var/log shows anything weird and it doesn't exactly have lots of built-in monitoring tools. So I'm hoping someone here could give me some pointers about what to look out for. I did change the ethernet cable from the office switch to the firewall, with no results. I might change switches, although within the switch it seems to work ok enough. Edit: I'm not sure whether this is the sole cause of the problem, but after I noticed a few DHCP entries just before the last drop of connectivity, I tried to reproduce that. And alas, whenever I renew a DHCP connection, I can't access other subnets anymore. Running ISC DHCPD 3.0.6.

Read the article
IPv6 Addresses causing Exchange Relay whitelists to fail

- by makerofthings7

Several of our new Exchange servers are failing to relay messages because it is communicating over IPv6 and not matching any receive connector I previously set up. I'm not sure how we are using IP6 since we only have a IPv4 network and we are routing across subnets. I discovered this by typing helo in from the source to the server that is confused by my IP6 address. I saw the IPv6 message and the custom message I gave this receive connector. (connectors with more permission have a different helo) 220 HUB01 client helo asdf 250 HUB01.nfp.com Hello [fe80::cd8:6087:7b1e:99d4%11] More info about my environment: I have two dedicated Exchange forests each with a distinct purpose. They have no trust and only communicate by SMTP. They both share the same DNS infrastructure via stub zones. What are my options? This is my guess, but I'm no IPv6 expert so I don't know which one is the best option Disable IPv6 Add the IPv6 address to the whitelist (isn't that IP dynamic?) Tell Exchange to use IPv4 instead Figure out why we are using IPv6 instead of IP4

Read the article
How to route broadcast packets from machine with two network interfaces on same subnet

- by Syam

I run RHEL 5 and have two NICs on one machine connected to the same subnet: eth0 192.168.100.10 eth1 192.168.100.11 My application needs to receive and transmit UDP packets (both unicast & broadcast) via these interfaces. I've found the way to handle the ARP problem and I've added routes to handle the routing problem: ip rule add from 192.168.100.10 lookup 10 ip route add table 10 default src 192.168.100.10 dev eth0 (and similarly, table 11 for eth1) The problem is that only unicast packets gets routed properly. Broadcast packets always go out through eth0. I tried removing the rule for 192.168.100.0 & 192.168.100.255 from table 255 and adding them to my tables. But then I see ARP requests being given out for packets to 192.168.100.255 (obviously, no nodes respond and nobody gets any data). Due to several techno-political issues, I'm stuck with this configuration and can't change subnets or try something different. I've tried SO_BINDTODEVICE and it works, but I'd prefer a solution that doesn't need my application to run as root. Is there a way to get this working? Any help is highly appreciated.

Read the article
Slow tracepath on local LAN

- by Simone Falcini

I am on EXSi and I have 2 instances: Ubuntu and CentOS. These are the network configurations Ubuntu eth0 Link encap:Ethernet HWaddr 00:50:56:00:1f:68 inet addr:212.83.153.71 Bcast:212.83.153.71 Mask:255.255.255.255 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:76059 errors:0 dropped:26 overruns:0 frame:0 TX packets:7224 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:6482760 (6.4 MB) TX bytes:2080684 (2.0 MB) eth1 Link encap:Ethernet HWaddr 00:0c:29:46:5a:f2 inet addr:192.168.1.1 Bcast:192.168.1.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:252 errors:0 dropped:0 overruns:0 frame:0 TX packets:608 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:42460 (42.4 KB) TX bytes:82474 (82.4 KB) /etc/iptables.conf *nat :PREROUTING ACCEPT [142:12571] :INPUT ACCEPT [5:1076] :OUTPUT ACCEPT [8:496] :POSTROUTING ACCEPT [8:496] -A POSTROUTING -s 192.168.1.0/24 -o eth0 -j MASQUERADE COMMIT *filter :INPUT ACCEPT [2:72] :FORWARD ACCEPT [4:336] :OUTPUT ACCEPT [6:328] -A INPUT -i eth1 -p tcp -j ACCEPT -A INPUT -i eth1 -p udp -j ACCEPT -A INPUT -i eth0 -p tcp --dport ssh -j ACCEPT COMMIT CentOS eth0 Link encap:Ethernet HWaddr 00:0C:29:74:1C:55 inet addr:192.168.1.2 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::20c:29ff:fe74:1c55/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:499 errors:0 dropped:0 overruns:0 frame:0 TX packets:475 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:68326 (66.7 KiB) TX bytes:82641 (80.7 KiB) The main problem is that if i execute this command from the CentOS instance ssh 192.168.1.2 it takes more than 20s to connect. It seems like it's routing the connection to the wrong network. What could it be? Thanks!

Read the article
Fortigate restrict traffic through one external IP

- by Tom O'Connor

I've got a fortigate 400A at a client's site. They've got a /26 from British Telecom, and we're using 4 of those IPs as a NAT Pool. Is there a way to say that traffic from 172.18.4.40-45 can only ever come out of (and hence go back into) x.x.x.140 as the external IP? We're having some problems with SIP which looks like it's coming out of one, and trying to go back into another. I tried enabling asymmetric routing, didn't work. I tried setting a VIP, but even when I did that, it didn't appear to do anything. Any ideas? I can probably post some firewall snippets if need be.. Tell me what you want to see. SIP ALG config system settings set sip-helper disable set sip-nat-trace disable set sip-tcp-port 5061 set sip-udp-port 5061 set multicast-forward enable end Interesting Sidenote VoIP phones, with no special configuration can register fine to proxy.sipgate.co.uk, which has an IP address of 217.10.79.16. Which is cool. Two phones are using a different provider, whose proxy IP address is 178.255.x.x. These phones can register for outbound, but inbound INVITEs never make it to the phone. Is it possible that the Fortigate is having trouble with 178.255.x.x as it's got a 255 in it? Or am I just imagining things?

Read the article
Route web traffic through a separate iterface

- by tkane

I'd like to route web traffic through the wlan0 interface and the rest through eth1. Can you please help me with the iptables commands to achieve this. Below is my configuration. Thank you :) Edit: This is about desktop configuration not a web server set up. Basically I want to use one of my connections to browse the web and the other one for everything else. ifconfig: eth1 Link encap:Ethernet HWaddr 00:1d:09:59:80:70 inet addr:192.168.2.164 Bcast:192.168.2.255 Mask:255.255.255.0 inet6 addr: fe80::21d:9ff:fe59:8070/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:33 errors:0 dropped:0 overruns:0 frame:0 TX packets:41 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:4771 (4.7 KB) TX bytes:7081 (7.0 KB) Interrupt:17 wlan0 Link encap:Ethernet HWaddr 00:1c:bf:90:8a:6d inet addr:192.168.1.70 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::21c:bfff:fe90:8a6d/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:77 errors:0 dropped:0 overruns:0 frame:0 TX packets:102 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:14256 (14.2 KB) TX bytes:14764 (14.7 KB) route: Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 192.168.2.0 * 255.255.255.0 U 1 0 0 eth1 192.168.1.0 * 255.255.255.0 U 2 0 0 wlan0 link-local * 255.255.0.0 U 1000 0 0 wlan0 default adsl 0.0.0.0 UG 0 0 0 eth1

Read the article
Route web browsing through a separate iterface

- by tkane

I'd like to route web browsing through the wlan0 interface and the rest through eth1. Can you please help me with the iptables commands to achieve this. Below is my configuration. Thank you :) Edit: This is about desktop configuration not a web server set up. Basically I want to use one of my connections to browse the web and the other one for everything else. ifconfig: eth1 Link encap:Ethernet HWaddr 00:1d:09:59:80:70 inet addr:192.168.2.164 Bcast:192.168.2.255 Mask:255.255.255.0 inet6 addr: fe80::21d:9ff:fe59:8070/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:33 errors:0 dropped:0 overruns:0 frame:0 TX packets:41 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:4771 (4.7 KB) TX bytes:7081 (7.0 KB) Interrupt:17 wlan0 Link encap:Ethernet HWaddr 00:1c:bf:90:8a:6d inet addr:192.168.1.70 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::21c:bfff:fe90:8a6d/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:77 errors:0 dropped:0 overruns:0 frame:0 TX packets:102 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:14256 (14.2 KB) TX bytes:14764 (14.7 KB) route: Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 192.168.2.0 * 255.255.255.0 U 1 0 0 eth1 192.168.1.0 * 255.255.255.0 U 2 0 0 wlan0 link-local * 255.255.0.0 U 1000 0 0 wlan0 default adsl 0.0.0.0 UG 0 0 0 eth1

Read the article
Packet flooding while configuring a Debian L2TP/IPSec client?

- by Joseph B.

I'm currently at my wits end trying to configure an L2TP over IPSec VPN connection on my Debian using openswan and xl2tp box connecting to a server of unknown configuration. I've managed to successfully establish the connection and everything appears to be working well until I attempt to set the VPN connection as my default route, at which point I see a massive flood of packets simultaneously being transmitted (on the tune of ~1.5 GB in about 2min) until the server drops my connection. Prior to this network traffic on all my interfaces is minimal. According to iftop the majority of this traffic appears to be coming out of port 12, although I can't seem to figure out how to finger a specific process. If I instead just route traffic destined for 74.0.0.0/8 through it I'm able to access Google's servers through the VPN without issue. My xl2tp.conf file is: [lac vpn-nl] lns = example.vpn.com name = myusername pppoptfile = /etc/ppp/options.l2tpd.client My options.l2tpd.client file is: ipcp-accept-local ipcp-accept-remote refuse-eap require-mschap-v2 noccp noauth idle 1800 mtu 1410 mru 1410 usepeerdns lock name myusername password mypassword connect-delay 5000 And my routing table looks like: Destination Gateway Genmask Flags Metric Ref Use Iface 10.5.2.1 * 255.255.255.255 UH 0 0 0 ppp0 10.0.50.0 * 255.255.255.0 U 0 0 0 eth0 10.50.0.0 * 255.255.0.0 U 0 0 0 eth0 10.0.0.0 * 255.255.0.0 U 0 0 0 eth0 192.168.0.0 * 255.255.0.0 U 0 0 0 eth0 loopback * 255.0.0.0 U 0 0 0 lo default * 0.0.0.0 U 0 0 0 ppp0 I'm seeing absolutely nothing in auth.log and syslog during this time and can't seem to find any other log files it might be writing to. Any suggestions would be appreciated!

Read the article
Preventing endless forwarding with two routers

- by jarmund

The network in quesiton looks basically like this: /----Inet1 / H1---[111.0/24]---GW1---[99.0/24] \----GW2-----Inet2 Device explaination H1: Host with IP 192.168.111.47 GW1: Linux box with IPs 192.168.111.1 and 192.168.99.2, as well as its own route to the internet. GW2: Generic wireless router with IP 192.168.99.1 and its own route to the internet. Inet1 & Inet2: Two possible routes to the internet In short: H has more than one possible route to the internet. H is supposed to only access the internet via GW2 when that link is up, so GW1 has some policy based routing special just for H1: ip rule add from 192.168.111.47 table 991 ip route add default via 192.168.99.1 table 991 While this works as long as GW2 has a direct link to the internet, the problem occurs when that link is down. What then happens is that GW2 forwards the packet back to GW1, which again forwards back to GW2, creating an endless loop of TCP-pingpong. The preferred result would be that the packet was just dropped. Is there something that can be done with iptables on GW1 to prevent this? Basically, an iptables-friendly version of "If packet comes from GW2, but originated from H1, drop it" Note1: It is preferable not to change anything on GW2. Note2: H1 needs to be able to talk to both GW1 and GW2, and vice versa, but only GW2 should lead to the internet TLDR; H1 should only be allowed internet access via GW2, but still needs to be able to talk to both GW1 and GW2. EDIT: The interfaces for GW1 are br0.105 for the '99' network, and br0.111 for the '111' network. The sollution may or may not be obnoxiously simple, but i have not been able to produce the proper iptables syntax myself, so help would be most appreciated. PS: This is a follow-up question from this question

Read the article
Linksys SFE2000 Interface

- by boburob

I have a real problem with a layer 3 Linksys switch. First, every time it looses power, it seems to reset back to an older config. Not only this, but when this happens it looses interface settings on one subnet. This would not be a problem but I am completely unable to get to the interface on the working side. It allows me to log on and then just displays a blank screen. I have tried this on: IE6 IE7 IE8 IE9 Firefox 3.5 Opera Chrome All with the same results, except for Opera, which loads half the interface but nothing I can really use. I really need to get onto this switch so I can sort out routing and VLAN tagged ports, so if anyone has any ideas on either of these issues please let me know ASAP! Thanks! Also, due to its location and my lack of laptops with serial connections I cannot putty into it. UPDATE: Looked into this a bit more and it looks like this model of switch does not save the current config to boot unless you make sure to save it yourself, which explains the first issue, however the broken interface is more worrying!

Read the article
Service redirection on same network

- by Unode

I have a network on which I run multiple servers each dedicated to a given service. Because most services run on distinct ports I'm currently looking for a way of unifying "all" services into a single "proxy" machine. The idea is to abstract which machine is being accessed but still allow direct connection if needed/requested. This "proxy" machine has only one network interface which is part of the same network as all the other service providing machines. I've looked into Routing and NAT but I've so far failed to figure out how to make it work. I tried to achieve this using shorewall but couldn't find clear examples. However I'm not entirely sure this is the best/simplest strategy. With that said, what would be the best way of achieving this result? Example case: Proxy IP - Listening port - Send requests to 192.168.0.50 80 192.168.0.1:80 " 22 192.168.0.2:2222 " 3306 192.168.0.3:3000 " 5432 192.168.0.4:5432 " 5222 192.168.0.5:5222 PS: I'm not concerned with the single-point-of-failure nature of the proxy. Thanks

Read the article
Linux: Three default gateways?

- by Daniel

My server has three default gateways, how can that be? Shouldn't there be one default gw? I have three NICs, each attached to a separate subnet: server1:~# route Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 10.5.0.0 * 255.255.255.224 U 0 0 0 eth3 localnet * 255.255.255.224 U 0 0 0 eth0 192.168.8.0 * 255.255.255.192 U 0 0 0 eth1 default 10.5.0.1 0.0.0.0 UG 0 0 0 eth3 default 192.168.8.1 0.0.0.0 UG 0 0 0 eth1 default 10.1.0.1 0.0.0.0 UG 0 0 0 eth0 Sometimes, I can't ping a host on the Internet, sometimes I can. What I want is traffic to the Internet (0.0.0.0) routed through a specific NIC. Can I just add a route for 0.0.0.0 and default gw to one of the eth0-3 interfaces? Will it break my connection? I'm using Debian, here is my /etc/network/interfaces: # This file describes the network interfaces available on your system # and how to activate them. For more information, see interfaces(5). # The loopback network interface auto lo iface lo inet loopback # The primary network interface allow-hotplug eth0 iface eth0 inet static address 10.1.0.4 netmask 255.255.255.224 network 10.1.0.0 broadcast 10.1.0.31 gateway 10.1.0.1 allow-hotplug eth1 iface eth1 inet static address 192.168.8.4 netmask 255.255.255.192 network 192.168.8.0 broadcast 192.168.8.63 gateway 192.168.8.1 allow-hotplug eth3 iface eth3 inet static address 10.5.0.4 netmask 255.255.255.224 network 10.5.0.0 broadcast 10.5.0.31 gateway 10.5.0.1

Read the article
Cisco 800 series won't forward port

- by sam

Hello ServerFault, I am trying to forward port 444 from my cisco router to my Web Server (192.168.0.2). As far as I can tell, my port forwarding is configured correctly, yet no traffic will pass through on port 444. Here is my config: ! version 12.3 service config no service pad service tcp-keepalives-in service tcp-keepalives-out service timestamps debug uptime service timestamps log uptime service password-encryption no service dhcp ! hostname QUESTMOUNT ! logging buffered 16386 informational logging rate-limit 100 except warnings no logging console no logging monitor enable secret 5 -removed- ! username administrator secret 5 -removed- username manager secret 5 -removed- clock timezone NZST 12 clock summer-time NZDT recurring 1 Sun Oct 2:00 3 Sun Mar 3:00 aaa new-model ! ! aaa authentication login default local aaa authentication login userlist local aaa authentication ppp default local aaa authorization network grouplist local aaa session-id common ip subnet-zero no ip source-route no ip domain lookup ip domain name quest.local ! ! no ip bootp server ip inspect name firewall tcp ip inspect name firewall udp ip inspect name firewall cuseeme ip inspect name firewall h323 ip inspect name firewall rcmd ip inspect name firewall realaudio ip inspect name firewall streamworks ip inspect name firewall vdolive ip inspect name firewall sqlnet ip inspect name firewall tftp ip inspect name firewall ftp ip inspect name firewall icmp ip inspect name firewall sip ip inspect name firewall fragment maximum 256 timeout 1 ip inspect name firewall netshow ip inspect name firewall rtsp ip inspect name firewall skinny ip inspect name firewall http ip audit notify log ip audit po max-events 100 ip audit name intrusion info list 3 action alarm ip audit name intrusion attack list 3 action alarm drop reset no ftp-server write-enable ! ! ! ! crypto isakmp policy 1 authentication pre-share ! crypto isakmp policy 2 encr 3des authentication pre-share group 2 ! crypto isakmp client configuration group staff key 0 qS;,sc:q<skro1^, domain quest.local pool vpnclients acl 106 ! ! crypto ipsec transform-set tr-null-sha esp-null esp-sha-hmac crypto ipsec transform-set tr-des-md5 esp-des esp-md5-hmac crypto ipsec transform-set tr-des-sha esp-des esp-sha-hmac crypto ipsec transform-set tr-3des-sha esp-3des esp-sha-hmac ! crypto dynamic-map vpnusers 1 description Client to Site VPN Users set transform-set tr-des-md5 ! ! crypto map cm-cryptomap client authentication list userlist crypto map cm-cryptomap isakmp authorization list grouplist crypto map cm-cryptomap client configuration address respond crypto map cm-cryptomap 65000 ipsec-isakmp dynamic vpnusers ! ! ! ! interface Ethernet0 ip address 192.168.0.254 255.255.255.0 ip access-group 102 in ip nat inside hold-queue 100 out ! interface ATM0 no ip address no atm ilmi-keepalive dsl operating-mode auto ! interface ATM0.1 point-to-point pvc 0/100 encapsulation aal5mux ppp dialer dialer pool-member 1 ! ! interface Dialer0 bandwidth 640 ip address negotiated ip access-group 101 in no ip redirects no ip unreachables ip nat outside ip inspect firewall out ip audit intrusion in encapsulation ppp no ip route-cache no ip mroute-cache dialer pool 1 dialer-group 1 no cdp enable ppp pap sent-username -removed- password 7 -removed- ppp ipcp dns request crypto map cm-cryptomap ! ip local pool vpnclients 192.168.99.1 192.168.99.254 ip nat inside source list 105 interface Dialer0 overload ip nat inside source static tcp 192.168.0.2 444 interface Dialer0 444 ip nat inside source static tcp 192.168.0.51 9000 interface Dialer0 9000 ip nat inside source static udp 192.168.0.2 1433 interface Dialer0 1433 ip nat inside source static tcp 192.168.0.2 1433 interface Dialer0 1433 ip nat inside source static tcp 192.168.0.2 25 interface Dialer0 25 ip classless ip route 0.0.0.0 0.0.0.0 Dialer0 ip http server no ip http secure-server ! ip access-list logging interval 10 logging 192.168.0.2 access-list 1 remark The local LAN. access-list 1 permit 192.168.0.0 0.0.0.255 access-list 2 permit 192.168.0.0 access-list 2 remark Where management can be done from. access-list 2 permit 192.168.0.0 0.0.0.255 access-list 3 remark Traffic not to check for intrustion detection. access-list 3 deny 192.168.99.0 0.0.0.255 access-list 3 permit any access-list 101 remark Traffic allowed to enter the router from the Internet access-list 101 permit ip 192.168.99.0 0.0.0.255 192.168.0.0 0.0.0.255 access-list 101 deny ip 0.0.0.0 0.255.255.255 any access-list 101 deny ip 10.0.0.0 0.255.255.255 any access-list 101 deny ip 127.0.0.0 0.255.255.255 any access-list 101 deny ip 169.254.0.0 0.0.255.255 any access-list 101 deny ip 172.16.0.0 0.15.255.255 any access-list 101 deny ip 192.0.2.0 0.0.0.255 any access-list 101 deny ip 192.168.0.0 0.0.255.255 any access-list 101 deny ip 198.18.0.0 0.1.255.255 any access-list 101 deny ip 224.0.0.0 0.15.255.255 any access-list 101 deny ip any host 255.255.255.255 access-list 101 permit tcp 67.228.209.128 0.0.0.15 any eq 1433 access-list 101 permit tcp host 120.136.2.22 any eq 1433 access-list 101 permit tcp host 123.100.90.58 any eq 1433 access-list 101 permit udp 67.228.209.128 0.0.0.15 any eq 1433 access-list 101 permit udp host 120.136.2.22 any eq 1433 access-list 101 permit udp host 123.100.90.58 any eq 1433 access-list 101 permit tcp any any eq 444 access-list 101 permit tcp any any eq 9000 access-list 101 permit tcp any any eq smtp access-list 101 permit udp any any eq non500-isakmp access-list 101 permit udp any any eq isakmp access-list 101 permit esp any any access-list 101 permit tcp any any eq 1723 access-list 101 permit gre any any access-list 101 permit tcp any any eq 22 access-list 101 permit tcp any any eq telnet access-list 102 remark Traffic allowed to enter the router from the Ethernet access-list 102 permit ip any host 192.168.0.254 access-list 102 deny ip any host 192.168.0.255 access-list 102 deny udp any any eq tftp log access-list 102 permit ip 192.168.0.0 0.0.0.255 192.168.99.0 0.0.0.255 access-list 102 deny ip any 0.0.0.0 0.255.255.255 log access-list 102 deny ip any 10.0.0.0 0.255.255.255 log access-list 102 deny ip any 127.0.0.0 0.255.255.255 log access-list 102 deny ip any 169.254.0.0 0.0.255.255 log access-list 102 deny ip any 172.16.0.0 0.15.255.255 log access-list 102 deny ip any 192.0.2.0 0.0.0.255 log access-list 102 deny ip any 192.168.0.0 0.0.255.255 log access-list 102 deny ip any 198.18.0.0 0.1.255.255 log access-list 102 deny udp any any eq 135 log access-list 102 deny tcp any any eq 135 log access-list 102 deny udp any any eq netbios-ns log access-list 102 deny udp any any eq netbios-dgm log access-list 102 deny tcp any any eq 445 log access-list 102 permit ip 192.168.0.0 0.0.0.255 any access-list 102 permit ip any host 255.255.255.255 access-list 102 deny ip any any log access-list 105 remark Traffic to NAT access-list 105 deny ip 192.168.0.0 0.0.0.255 192.168.99.0 0.0.0.255 access-list 105 permit ip 192.168.0.0 0.0.0.255 any access-list 106 remark User to Site VPN Clients access-list 106 permit ip 192.168.0.0 0.0.0.255 any dialer-list 1 protocol ip permit ! line con 0 no modem enable line aux 0 line vty 0 4 access-class 2 in transport input telnet ssh transport output none ! scheduler max-task-time 5000 ! end any ideas? :)

Read the article
Convert Spanned Dynamic disk to Basic Help needed.

- by Mouradb

Hello all, Here is my scenario; Windows 2008 server on a VM Two VM disks; Disk1 OS Basic Disk2 Data and an Installed Application. Basic Durng the weekend, I was playing with this VM, I wanted to add some space to the Disk2. Created a new disk (disk3), converted it to a Dynamic volum and added this to disk 2 (disk 2 also converted to Dynamic volume) and for some reason these now are spanned volumes. just like an IDOT, I haven't taken any snapshot of this before I've made the changes. My question, is there a way I can re-convert this again to Basic? I don't want to delete and recreate the disk volumes because of the application installed on the disk 2 Any solution or tips I can use?

Read the article

< Previous Page | 57 58 59 60 61 62 63 64 65 66 67 68 | Next Page >