Symptom: customer complains about slow response to SSH server running on one Centos box Method: perform packet capture on the SSH server. Finding: DNS query fails during establishing SSH session When folllow the TCP session for SSH login packet caoture, see the below: During packet 17 and 24, there is about 10 seconds gap. Go …
Continue reading Packet Analysis for Troubleshooting-SSH server slow response
Symptom: virtual desktop end users complain the performance issue: the end users can access their AD home directory quickly at the first time. After a little while, they have to wait for over 30 seconds before they can reach their home directory. Method: perform packet capture on one of end users and successfully capture the …
Continue reading Packet Analysis for Troubleshooting-Slow response of AD home directory
The BGP Multipath Load Sharing for eBGP and iBGP feature allows you to configure multipath load balancing with both external BGP (eBGP) and internal BGP (iBGP) paths. Vyatta OS supports both iBGP and eBGP Multipath. Regarding the load sharing, traffic load is shared across them on a per session basis. That is, each new session is routed …
Vyatta provides the capability to maintain connectivity through one IPsec tunnel by using a pair of Vyatta routers with VRRP. When one Vyatta router fails or is brought down for maintenance, the new VRRP master Vyatta router restores IPsec connectivity between the local and remote networks. Here I will show you how to configure the …
Firstly, what's LFN? LFN means long fat network, often pronounced "elephan". In RFC 1072, a network is considered an LFN if its bandwidth-delay product is significantly larger than 105 bits (12500 bytes). Then you will possibly have another question: what bandwidth-delay product is? As Wiki suggested, bandwidth-delay product refers to the product of a data …
Continue reading How to achieve maximum TCP throughput on LFN
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