During analysis of my ESX server, vsphere client communication I have encountered the following packet capture. My vsphere client keeps asking for a lost segment with ACK number 1583183 for 9 times after which according to wireshark analysis TCP Fast Retransmission which is one of the ways of handling congestion is engaged. When I check
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If you have a restricted policy that you have enforced for your internal clients but you want to allow traceroute requests from your internal clients towards another network you can do it as follows I suppose. You can create the following application and apply it on your security policy. [edit applications] root@srx100-1# application custom-traceroute {
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I am going to analyse a simple HTTP request response at packet level from application layer down to data link layer in this post. I took a sample packet capture by connecting to my web page which displays only “Hello World!” on an Apache web server. There are 10 ethernet frames captured and I will
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There are a couple of handy commands which you can use if you have a JSRP cluster. For example following two commands can be used for copying a file or directory e.g from node0 to node1 : >file copy /tmp/test_file.txt node1:/tmp/ %rcp -T /tmp/test_file.txt node1:/tmp/ If you want to copy directory you should also include
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When I was looking at one of my earlier posts, I noticed that sometimes I do repeat cli commands manually instead of scripting. Life is short! If you can’t find any other shell, junos has also C shell and following is a simple loop which generates several commands following a similar pattern. For example I
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I wasn’t planning to put my notes about packet capture here today but I have got an issue with my ESX server file upload component. I kept receiving “I/O Error” during a file upload to datastore directly or big (e.g 1-2 GB) ova file deployments. I took several captures with no positive result in the
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If you want to prevent root user being used in ssh logins, one command is sufficient to accomplish this. After commit, root user will be rejected and you can login with any other super-user. #set system services ssh root-login deny
If you want to mirror traffic entering and exiting a specific port (e.g ge-0/0/11.0) you can use the following configuration to mirror the traffic to any other port (e.g ge-0/0/10.0) Here is the configuration I wrote in an ex2200 switch. Port mirroring in EX switches [edit ethernet-switching-options analyzer port-mirror] root@ex2200-1# show input { ingress {
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I would like to show an example how we can use native vlan id in an EX switch. Normally if you set the port mode of an interface as trunk in EX switch, untagged traffic can’t pass through this interface. You have to tell Junos how it should behave on untagged frames. This is my
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It is a wonderful experience to be able to manage and monitor your hardware independently from the host OS. This post is just about a few commands I use to manage BMC (or whatever you call it) on my PC. It was surprising for me to see that I can use the same ethernet interface
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