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29

Default route (aka gateway address) has to be owned by something that is capable of forwarding packets to the rest of the internet, and which is willing to do so. It doesn't have to be the "principal" IP address of the thing that owns it (whatever that means). It can be a logical address that floats between two or more devices, and in high-availability ...


21

No they are not the same. Internet Gateway Routes traffic from instances with Public IPs to the Internet. It simply forwards traffic between Public IPs in your VPC and Public IPs in the internet back and forth, mostly unchanged. Gateways can sometimes be called routers but AWS doesn't use this term. NAT Gateway Routes traffic from instances with only ...


20

The netmask is wrong on the enp4s1 (WAN) interface. This system has configured an IP address of 49.x.x.x and a netmask of 255.0.0.0 (prefix /8). But this is not the netmask that your ISP gave you. As a result, you will be unable to access almost all websites whose IP addresses also start with 49. To resolve the problem, fix the netmask or prefix ...


19

A gateway and a router are essentially the same. The term "default gateway" is used to mean the router on your LAN which has the responsibility of being the first point of contact for traffic to computers outside the LAN. If your LAN has multiple routers, the router designated as a default gateway can notify your computer, using an ICMP redirect or other ...


16

Here how it resolved my issue: make following changes to /etc/nginx/nginx.conf in http { section proxy_connect_timeout 600s; proxy_send_timeout 600s; proxy_read_timeout 600s; fastcgi_send_timeout 600s; fastcgi_read_timeout 600s; and then restart nginx /etc/init.d/nginx restart


15

The IP address of the gateway can be any valid host IP address in the subnet, i.e. not the network address itself nor the broadcast address. This IP address does not need to belong to a single computer or router, it can be a "floating" IP address used by several gateways. Check out the Wikipedia articles on HSRP, VRRP, GLBP, or CARP. For example, when the ...


9

Yes, you should use fastcgi_read_timeout. You can find documentation here. According to that, you can specify this parameter either in http, server or location context. So it is also possible to put in into fastcgi.conf and include that file where you setup FastCGI.


9

"Logical entity" in your usage is a tiny bit confusing. But I'll try to answer it best I can. From my experience, a gateway in an IP configuration is usually a physical device. While it doesn't have to be a computer in the traditional sense (it can also be a network appliance) it does have to be device. As you may know, the purpose that a default gateway ...


7

You can't drop ICMP fragmentation required messages. They're required for pMTU discovery, which is required for TCP to work properly. Please LART the firewall administrator. By the transparency rule, a packet-filtering router acting as a firewall which permits outgoing IP packets with the Don't Fragment (DF) bit set MUST NOT block incoming ICMP ...


6

This is an old thread, but here goes. As it happens, I run a number of OpenBSD VMs on an ESXi 6.0 running at SoYouStart, a daughter company of OVH. The network setup there is the same as with OVH and I think, although strange, its main purpose is to eliminate ARP traffic as much as possible by artificially limiting the broadcast domains, and without the ...


5

@RedGrittyBrick is absolutely correct with his answer ("a router and a gateway are essentially the same"), some other responders are confusing the terms or, to put it kindly, have misunderstood the question (or wikipedia). As far as routing goes the term "gateway" is almost only ever used in conjunction with "default", and that "gateway" provides a route to ...


5

There is not enough detail in this question to provide a complete solution; however there are some general principles I can share which you might be able to research on your own and apply. The relevant details include: Router / Firewall models Resilience & recovery time in the face of link / equipment failure Topology Future plans for expansion ...


5

Use a router that connects to both ISPs and can handle the fail-over between ISPs when one goes down.


5

Use a dual-WAN router. On the low-end, the TP-LINK TL-R470T+ is around $60. On the higher end, consider the Cisco RV042. Update: Some of the other answers suggest using a PC as a router. This is a more powerful and flexible solution. But it requires a lot more knowledge and effort on your part. If you don't have anyone available who is familiar with IP ...


5

Firstly, I would hazard a guess that 90% of the time it's the first IP address in your subnet (so, 10.10.5.0/24, it would be 10.10.5.1) - although my network has one on .17 and one on .23 (and nothing at all on .1); so make of that what you will. If it's a wifi network, you could listen in promiscious mode and look at what the most common destination for ...


5

You were on the right track - use the full 192.168.0.0/16 subnet and you'll have access to plenty of ip addresses (64k). You'll need to expand your DHCP server to publish these addresses and possibly change your netmask to 16 (255.255.0.0) rather than 24 (255.255.255.0) http://jodies.de/ipcalc?host=192.168.0.1&mask1=16&mask2=


5

You have the FORWARD filter set to DROP. So iptables is dropping all forwarding. If you want to keep it set to DROP, you need to add the following rule iptables -I FORWARD -i eth0 -s 192.168.0.0/24 -j ACCEPT iptables -I FORWARD -i eth1 -d 192.168.0.0/24 -j ACCEPT


5

You don't say what your gateway is, but my vote is that this is a router/gateway issue. Most likely the arp entry on the gw is timing out and not getting refreshed, or there is another device on the network responding to arps for your server's ip address or is gratuitously arpping your server's address. When you ping the gateway, it looks in it's arp ...


5

Depends if you want that system to be able to communicate outside its subnet. If not, then it doesn't matter what you set the gateway to. But yes, the default gateway should be set to the router's LAN interface, unless you have an L3 switch with proper routing set up, in which case the default gateway would likely be one of the SVIs on the switch. With an ...


5

What is the purpose of that -w 3 in the original solution It avoids leaving orphaned nc processes running on the remote host when the ssh session is closed improperly. and why is it causing a Broken pipe error when I use it? Try increasing the timeout for nc to 90 and setting ServerAliveInterval to 30 to see if your problem go away: host foo User ...


5

Your alternative approach could be achieved by using policy based routing. Something along the lines of (commands should be executed on GW1): # Create rule for matching the source address in route table 999 ip rule add from 1.2.3.4/32 table 999 # Add default router to the table ip route add default via <GW2> table 999 I don't have the possibility to ...


5

Ok, this can be done, but it's definitely not as easy as it could (and should) be. Basically, the trick is using Azure's "local networks" to configure Azure gateways as we want, even if we can't directly touch their configuration. In order to set up a connection between two Azure virtual networks, you need to define two matching "local networks", and then ...


5

It stands to reason that the syntax in the question would make sense. However, it is even simpler than that: dhcp-option=eth0,3,10.1.0.254 dhcp-option=eth1,3,10.1.20.254 [Edit] After a couple years of this in use, I'm reporting a problem with this setup. Say you have a public and a secure network, both accessible via WiFi. If your device connects to the ...


5

No, there really is no such thing.


5

Routing table entries resolve a subnet to either a gateway or a network adapter. A typical routing table for a device on a private network might, if you leave out the unnecessary stuff, look like 0.0.0.0/0 via 192.168.0.1 192.168.0.0/24 dev eth0 The most specific route wins for each destination, so the subnet route takes precedence over the default route ...


4

For transparent Git/Svn gateway you may use SubGit, it matches your requirements very well, except that right now it only supports either simple single-project (/trunk, /branches, /tags) or multi-project (/project/trunk, ...) layouts.


4

If you do not know how to build one, you will need to purchase a network device (router) capable of load balancing between multiple ISPs. With inbound traffic, one solution would be to use a dynamic routing protocol such as BGP. With outbound traffic, a solution would be to failover a VIP between multiple devices using a protocol such as HSRP. If you do ...


4

You need to use NAT to share the internet connection to your LAN. Example: iptables --table nat --append POSTROUTING --out-interface eth0 -j MASQUERADE iptables --append FORWARD --in-interface eth1 -j ACCEPT See this guide at HowtoForge for more info: http://www.howtoforge.com/nat_iptables


4

You can use Cacti to graph switch port traffic with SNMP.


4

If the network is open (unencrypted) then yes; you can capture the full packets of connected clients and see the addresses in IP and ARP packets. If the network is encrypted, then no; all of the layer 3 communication is encapsulated in encrypted packets at all times, and the MAC addresses on the transmissions is all you can get without breaking the ...


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