marctxk
  • Member for 5 years, 6 months
  • Last seen more than 4 years ago
Internal NAT before establishing a VPN Host-to-Host
0 votes

In the situation of overlapping address ranges, if the source and destination are both in the overlapping range then you will need to NAT both source and destination IP addresses (twice-NAT) if you ...

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Getting "public" IP's while keeping firewall enabled
1 votes

If ou want to get traffic from the multi-tenant network to your own using the addresses given to you from the multi-tenant subnet you'll need to turn off NAT as you have done and then enable proxy-arp ...

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When ARP cache is updated?
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5 votes

If that were to happen just as you state, then your pings would fail. In practise if you are using DHCP to hand out addresses, the server will give you back the same address. Even if it doesn't (...

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Increasing the MTU size for 3G/LTE networks
5 votes

I think it's always best to allow end-user traffic to use an MTU of 1500. Therefore when encapsulated the overlay network has to cater for this either by a larger MTU size in the encapsulated domain ...

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ICMP Ping Request/Reply
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1 votes

It's a success if that's what you're expecting. All command-line ping programs I've seen will display where the replies have come from. If you send a braodcast ping you will often get multiple ...

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Packet sizes in a TCP stream
0 votes

If you look at frame 34, you will see that the server has transmitted a 32kB buffer and that the PSH bit is set. If you look at 82 you will see the same, 32 kB from the previous PSH bit. Packet 52 ...

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Why do we need "port forwording" if we can connect to the port ourselves?
2 votes

Port forwarding is not usually found in a true enterprise environment but may be used in a SOHO network when the router IP is the only public IP used. It enables incoming traffic to a certain port on ...

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How troubleshoot poor ipsec connection?
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3 votes

Normally you would first check whether all packets are being encapsulated and decapsulated OK by viewing ipsec counters on the tunnel endpoints. However if you want to look at packets, first you need ...

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Do we really need ARP when only hubs are used to connect devices?
0 votes

Peter and Jaap are both right but more fundamentally, we use a layered model to ensure interoperability between vendors. The MAC layer uses a MAC address, full-stop. ARP allows us to discover those ...

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Will Cat6 make a difference
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2 votes

Cat5e is fine for Gigabit Ethernet, so no it would not make a difference

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Abnormally Bandwidth utilization goes high what should I do
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2 votes

You should capture all network traffic from your internet connection to understand what traffic is causing it. Until you know what causes it, you cannot take effective action to stop it happening. ...

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Number of tcp connection accepts more than number of connection requests in output of netstat
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1 votes

I think you'll find it's showing incoming "accepts" and outgoing "requests"

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SNMP OID to detect network equipment vendor
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3 votes

No, there's not a single OID tree to describe the equipment. There is a vendor-specific tree, and each vendor implements their own MIB tree under that. Whether or not any particular vendor bothers (...

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Web server address with two ISPs
2 votes

Unfortunately BGP will not help you, this is small-scale. You will not be able to justify a provider-independent block of addresses for a single web server even if RIPE is still issuing them. ...

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How to measure the firewall latency?
Accepted answer
2 votes

I don't know your full circumstances, but if an accurate figure for device latency really mattered to me then I would hire specialised equipment for this task. I'm in the UK and there are specialist ...

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Should all sent segments be requeued after a TCP retransmission timeout expires?
1 votes

In your example 2000 and 3000 are transmitted "now". The retransmission timer is only there to signal the possiblity of lost packets, you've "been there done that" once you've started retransmission.

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How to practically measure end to end delay
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2 votes

The most accurate way that I can think of to measure round-trip network time between two TCP/IP endpoints is to capture network traffic using taps on the network interfaces of each, and use a large ...

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OSPF behavior on serial link, why neighborship formed even if interfaces belog from different network?
1 votes

OSPF hellos do not use the subnet address, they use multicast so they will be received by each router. I guess this should be off-topic since it's not an entreprise networking question.

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Suggestions; changing enterprise ISP + current MPLS routing
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1 votes

It is never possible to test a routing change until it has been implemented so the direct answer to your direct question is "no". But that's not really helpful. More generally, consider why you want ...

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BGP route traffic from iBGP over eBGP instead
Accepted answer
4 votes

By default R1 will drop the route to R2 received form R3 because the AS path contains R1's AS. On cisco you can use allowas-in to stop this default behaviour though I've never done this myself and I ...

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The difference between simple ACK and ACK aggregation improvement in TCP
0 votes

It's not a term I've come across, perhaps you could provide the reference. However most acks are aggregated for example during a steady-state data transfer, say a large file going in one direction. ...

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What could cause TCP to retransmit only the end of a (fully acknowledged) segment?
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2 votes

I think your capture is scooped due to some form of TCP segmenation offload on your host. I doubt that the packets appeared on the wire as shown. Notice that frame 11 has a reported length of 1714 ...

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Adding a private network - basic question
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3 votes

The configuration you want is fine, there will be no default gateway on that subnet, so for instance on a Windows host or Linux GUI that field would be left blank in the network setup.

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Why are the computer systems in the OSI model called "open systems"?
2 votes

They are connected using open protocols as opposed to proprietary protocols (open as per open source). Back in the day, each vendor had their own interconnect technology, such as IBM's SNA and DEC's ...

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Why is there no "round robin" option for lacp (at least on my switches)?
2 votes

LACP controls the aggregation of links, it doesn't control switching. The selection of a particular member of a bundle is via an algortithm decided upon and implemented by each switch vendor. It has ...

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Wireshark Broadcast Storm
Accepted answer
1 votes

If you are capturing to memory only and stopping when the buffer runs out, then in the case of a broadcast storm the last frame time will be when the buffer ran out of memory. I'm not sure why you'd ...

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linux network card packet timestamping
2 votes

Some specialist network cards provide timestamping. The vendor will supply a driver so that network packet capture applications can access and store these timestamps. No normal business application ...

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Obtaining MAC address of an external IP
3 votes

No, there's no way of knowing and at a network level there's no point knowing. The MAC adddress belongs in layer-2. Obviously if you are responsible for the equipment, you may want to enter the ...

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What is the common notation of multiple subnets
0 votes

In all my days I've never seen anyone want to do this but if you really must have a technically correct description you need to use a mask, not CIDR notation and for all /29 nets I guess that would be ...

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When changing ISPs, do I have to order a new static IP address?
3 votes

You will not be able to reuse the current one, it will be part of your current ISP address range, and will not be portable to your new ISP

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